ASP.NET MVC下的四种验证编程方式
ASP.NET MVC采用Model绑定为目标Action生成了相应的参数列表，但是在真正执行目标Action方法之前，还需要对绑定的参数实施验证以确保其有效性，我们将针对参数的验证成为Model绑定。总地来说，我们可以采用4种不同的编程模式来进行针对绑定参数的验证。
一、手工验证绑定的参数
在定义具体Action方法的时候，对已经成功绑定的参数实施手工验证无疑是一种最为直接的编程方式，接下来我们通过一个简单的实例来演示如何将参数验证逻辑实现在对应的Action方法中，并在没有通过验证的情况下将错误信息响应给客户端。我们在一个ASP.NET MVC应用中定义了如下一个Person类作为被验证的数据类型，它的Name、Gender和Age三个属性分别表示一个人的姓名、性别和年龄。
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| | .keyword} Gender { {.csharp |
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| | .keyword}; }{.csharp .plain} |
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| | .spaces}[DisplayName({.csharp |
| | .plain}"年龄"{.csharp |
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| | .keyword}? Age { {.csharp |
| | .plain}get{.csharp |
| | .keyword}; {.csharp |
| | .plain}set{.csharp |
| | .keyword}; }{.csharp .plain} |
| | ::: |
| | |
| | ::: {.line .number11 .index10 .alt2} |
| | }{.csharp .plain} |
| | ::: |
| | :::::::::::::: |
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接下来我们定义了如下一个HomeController。在针对GET请求的Action方法Index中，我们创建了一个Person对象并将其作为Model呈现在对应的View中。另一个支持POST请求的Index方法具有一个Person类型的参数，我们在该Action方法中先调用Validate方法对这个输入参数实施验证。如果验证成功（ModeState.IsValid属性返回True），我们返回一个内容为"输入数据通过验证"的ContentResult，否则将此参数作为Model呈现在对应的View中。
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| | .keyword} HomeController : Controller{.csharp .plain} |
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| ::: {.line .number5 .index4 .alt2} | .keyword} ActionResult Index(){.csharp .plain} |
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| 7 | .keyword} View({.csharp .plain}new{.csharp |
| ::: | .keyword} Person());{.csharp .plain} |
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| ::: | {.csharp .spaces}}{.csharp .plain} |
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| | .keyword} ActionResult Index(Person person){.csharp .plain} |
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| ::: {.line .number13 .index12 .alt2} | ::: |
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| ::: | ::: {.line .number12 .index11 .alt1} |
| | {.csharp .spaces}Validate(person);{.csharp .plain} |
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| | {.csharp .spaces}if{.csharp |
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| ::: {.line .number18 .index17 .alt1} | {.csharp .spaces}return{.csharp |
| 18 | .keyword} View(person);{.csharp .plain} |
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| | |
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| 19 | {.csharp .spaces}}{.csharp .plain} |
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| ::: | ::: |
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| ::: {.line .number22 .index21 .alt1} | ::: {.line .number20 .index19 .alt1} |
| 22 | {.csharp .spaces}return{.csharp |
| ::: | .keyword} Content({.csharp .plain}"输入数据通过验证"{.csharp |
| | .string});{.csharp .plain} |
| ::: {.line .number23 .index22 .alt2} | ::: |
| 23 | |
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| | {.csharp .spaces}}{.csharp .plain} |
| ::: {.line .number24 .index23 .alt1} | ::: |
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| | {.csharp .spaces}}{.csharp .plain} |
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| | |
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| ::: | ::: {.line .number24 .index23 .alt1} |
| | {.csharp .spaces}private{.csharp |
| ::: {.line .number27 .index26 .alt2} | .keyword} void{.csharp |
| 27 | .keyword} Validate(Person person){.csharp .plain} |
| ::: | ::: |
| | |
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| 28 | {.csharp .spaces}{{.csharp .plain} |
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| 29 | {.csharp .spaces}if{.csharp .keyword} ({.csharp |
| ::: | .plain}string{.csharp |
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| 30 | |
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| 31 | |
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| | {.csharp |
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| 32 | .plain}"Name"{.csharp .string}, {.csharp |
| ::: | .plain}"'Name'是必需字段"{.csharp .string});{.csharp .plain} |
| | ::: |
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| 33 | ::: {.line .number29 .index28 .alt2} |
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| 35 | ::: {.line .number31 .index30 .alt2} |
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| | .plain}string{.csharp |
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| 36 | ::: |
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| 37 | ::: |
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| ::: {.line .number38 .index37 .alt1} | {.csharp |
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| | .plain}"'Gender'是必需字段"{.csharp .string});{.csharp |
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| 39 | ::: |
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| 40 | ::: |
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| | ::: {.line .number35 .index34 .alt2} |
| ::: {.line .number41 .index40 .alt2} | {.csharp .spaces}else{.csharp .keyword} if{.csharp |
| 41 | .keyword} (!{.csharp .plain}new{.csharp |
| ::: | .keyword} string{.csharp .keyword}[] { {.csharp |
| | .plain}"M"{.csharp .string}, {.csharp .plain}"F"{.csharp |
| ::: {.line .number42 .index41 .alt1} | .string} }.Any({.csharp .plain} |
| 42 | ::: |
| ::: | |
| | ::: {.line .number36 .index35 .alt1} |
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| 43 | .plain}string{.csharp |
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| | .plain}true{.csharp .keyword}) == 0)){.csharp .plain} |
| ::: {.line .number44 .index43 .alt1} | ::: |
| 44 | |
| ::: | ::: {.line .number37 .index36 .alt2} |
| | {.csharp .spaces}{{.csharp .plain} |
| ::: {.line .number45 .index44 .alt2} | ::: |
| 45 | |
| ::: | ::: {.line .number38 .index37 .alt1} |
| | {.csharp |
| ::: {.line .number46 .index45 .alt1} | .spaces}ModelState.AddModelError({.csharp |
| 46 | .plain}"Gender"{.csharp .string}, {.csharp .plain} |
| ::: | ::: |
| | |
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| 47 | {.csharp |
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| | .string});{.csharp .plain} |
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| 48 | |
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| 49 | |
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| | |
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| 50 | |
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| | {.csharp .spaces}if{.csharp .keyword} ({.csharp |
| ::: {.line .number51 .index50 .alt2} | .plain}null{.csharp .keyword} == person.Age){.csharp .plain} |
| 51 | ::: |
| ::: | |
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| | {.csharp .spaces}{{.csharp .plain} |
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| | {.csharp |
| | .spaces}ModelState.AddModelError({.csharp |
| | .plain}"Age"{.csharp .string}, {.csharp |
| | .plain}"'Age'是必需字段"{.csharp .string});{.csharp .plain} |
| | ::: |
| | |
| | ::: {.line .number45 .index44 .alt2} |
| | {.csharp .spaces}}{.csharp .plain} |
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| | |
| | ::: {.line .number46 .index45 .alt1} |
| | {.csharp .spaces}else{.csharp .keyword} if{.csharp |
| | .keyword} (person.Age > 25 || person.Age < 18){.csharp .plain} |
| | ::: |
| | |
| | ::: {.line .number47 .index46 .alt2} |
| | {.csharp .spaces}{{.csharp .plain} |
| | ::: |
| | |
| | ::: {.line .number48 .index47 .alt1} |
| | {.csharp |
| | .spaces}ModelState.AddModelError({.csharp |
| | .plain}"Age"{.csharp .string}, {.csharp |
| | .plain}"有效'Age'必须在18到25周岁之间"{.csharp |
| | .string});{.csharp .plain} |
| | ::: |
| | |
| | ::: {.line .number49 .index48 .alt2} |
| | {.csharp .spaces}}{.csharp .plain} |
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| | |
| | ::: {.line .number50 .index49 .alt1} |
| | {.csharp .spaces}}{.csharp .plain} |
| | ::: |
| | |
| | ::: {.line .number51 .index50 .alt2} |
| | }{.csharp .plain} |
| | ::: |
| | :::::::::::::::::::::::::::::::::::::::::::::::::::::: |
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如上面的代码片断所示，我们在Validate该方法中我们对作为参数的Person对象的3个属性进行逐条验证，如果提供的数据没有通过验证，我们会调用当前ModelState的AddModelError方法将指定的验证错误消息转换为ModelError保存起来。我们采用的具体的验证规则如下。
- Person对象的Name、Gender和Age属性均为必需字段，不能为Null（或者空字符串）。
- 表示性别的Gender属性的值必需是"M"（Male）或者"F"（Female），其余的均为无效值。
- Age属性表示的年龄必须在18到25周岁之间。
如下所示的是Action方法Index对应View的定义，这是一个Model类型为Person的强类型View，它包含一个用于编辑人员信息的表单。我们直接调用HtmlHelper<TModel> 的扩展方法EditorForModel将作为Model的Person对象以编辑模式呈现在表单之中。
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| ::: {.line .number1 .index0 .alt2} | :::::::::::::::: container |
| 1 | ::: {.line .number1 .index0 .alt2} |
| ::: | @model Person{.xml .plain} |
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| ::: | <{.xml .plain}html{.xml |
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| | <{.xml .plain}head{.xml |
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| 4 | ::: |
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| | ::: {.line .number4 .index3 .alt1} |
| ::: {.line .number5 .index4 .alt2} | {.xml .spaces}<{.xml |
| 5 | .plain}title{.xml |
| ::: | .keyword}>编辑人员信息</{.xml |
| | .plain}title{.xml .keyword}>{.xml |
| ::: {.line .number6 .index5 .alt1} | .plain} |
| 6 | ::: |
| ::: | |
| | ::: {.line .number5 .index4 .alt2} |
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| 7 | .keyword}>{.xml .plain} |
| ::: | ::: |
| | |
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| 8 | <{.xml .plain}body{.xml |
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| | ::: |
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| 9 | ::: {.line .number7 .index6 .alt2} |
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| 10 | ::: |
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| 11 | ::: |
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| ::: {.line .number12 .index11 .alt1} | {.xml |
| 12 | .spaces}@Html.EditorForModel(){.xml |
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| 13 | ::: {.line .number10 .index9 .alt1} |
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| | .plain}input{.xml |
| | .keyword} type{.xml .color1}={.xml |
| | .plain}"submit"{.xml |
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| | .plain} |
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| | |
| | ::: {.line .number11 .index10 .alt2} |
| | {.xml .spaces}}{.xml .plain} |
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| | |
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| | .keyword}>{.xml .plain} |
| | ::: |
| | |
| | ::: {.line .number13 .index12 .alt2} |
| | </{.xml .plain}html{.xml |
| | .keyword}>{.xml .plain} |
| | ::: |
| | :::::::::::::::: |
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::: {#scid:8747F07C-CDE8-481f-B0DF-C6CFD074BF67:46d997eb-46d6-4122-bb79-27130903682c .wlWriterEditableSmartContent}
直接运行该程序后，一个用于编辑人员基本信息的页面会被呈现出来，如果我们在输入不合法的数据并提交后，相应的验证信息会以图1所示的形式呈现出来。
二、使用ValidationAttribute特性
将针对输入参数的验证逻辑和业务逻辑定义在Action方法中并不是一种值得推荐的编程方式。在大部分情况下，同一个数据类型在不同的应用场景中具有相同的验证规则，如果我们能将验证规则与数据类型关联在一起，让框架本身来实施数据验证，那么最终的开发者就可以将关注点更多地放在业务逻辑的实现上面。实际上这也是ASP.NET MVC的Model验证系统默认支持的编程方式。当我们在定义数据类型的时候，可以在类型及其数据成员上面应用相应的ValidationAttribute特性来定义默认采用的验证规则。
"System.ComponentModel.DataAnnotations"命名空间定义了一系列具体的ValidationAttribute特性类型，它们大都可以直接应用在自定义数据类型的某个属性上对目标数据成员实施验证。这些预定义验证特性不是本章论述的重点，我们会在"下篇"中对它们作一个概括性的介绍。
常规验证可以通过上面列出的这些预定义ValidationAttribute特性来完成，但是在很多情况下我们需要通过创建自定义的ValidationAttribute特性来解决一些特殊的验证。比如上面演示实例中针对Person对象的验证中，我们要求Gender属性指定的表示性别的值必须是"M/m"和"F/f"两者之一，这样的验证就不得不通过自定义的ValidationAttribute特性来实现。
针对 "某个值必须在指定的范围内"这样的验证规则，我们定义一个DomainAttribute特性。如下面的代码片断所示，DomainAttribute具有一个IEnumerable<string>类型的只读属性Values提供了一个有效值列表，该列表在构造函数中被初始化。具体的验证实现在重写的IsValid方法中，如果被验证的值在这个列表中，则视为验证成功并返回True。为了提供一个友好的错误消息，我们重写了方法FormatErrorMessage。
:::: {#highlighter_544917 .syntaxhighlighter .csharp} ::: toolbar :::
+--------------------------------------+--------------------------------------------------------------------------------------------------+
| ::: {.line .number1 .index0 .alt2} | ::::::::::::::::::::::::::::::::: container |
| 1 | ::: {.line .number1 .index0 .alt2} |
| ::: | [AttributeUsage(AttributeTargets.Property | AttributeTargets.Field, AllowMultiple = {.csharp |
| | .plain}false{.csharp .keyword})]{.csharp .plain} |
| ::: {.line .number2 .index1 .alt1} | ::: |
| 2 | |
| ::: | ::: {.line .number2 .index1 .alt1} |
| | public{.csharp .keyword} class{.csharp |
| ::: {.line .number3 .index2 .alt2} | .keyword} DomainAttribute : ValidationAttribute{.csharp .plain} |
| 3 | ::: |
| ::: | |
| | ::: {.line .number3 .index2 .alt2} |
| ::: {.line .number4 .index3 .alt1} | {{.csharp .plain} |
| 4 | ::: |
| ::: | |
| | ::: {.line .number4 .index3 .alt1} |
| ::: {.line .number5 .index4 .alt2} | {.csharp .spaces}public{.csharp .keyword} IEnumerable<{.csharp .plain}string{.csharp |
| 5 | .keyword}> Values { {.csharp .plain}get{.csharp .keyword}; {.csharp |
| ::: | .plain}private{.csharp .keyword} set{.csharp .keyword}; }{.csharp .plain} |
| | ::: |
| ::: {.line .number6 .index5 .alt1} | |
| 6 | ::: {.line .number5 .index4 .alt2} |
| ::: | |
| | ::: |
| ::: {.line .number7 .index6 .alt2} | |
| 7 | ::: {.line .number6 .index5 .alt1} |
| ::: | {.csharp .spaces}public{.csharp .keyword} DomainAttribute({.csharp |
| | .plain}string{.csharp .keyword} value){.csharp .plain} |
| ::: {.line .number8 .index7 .alt1} | ::: |
| 8 | |
| ::: | ::: {.line .number7 .index6 .alt2} |
| | {.csharp .spaces}{{.csharp .plain} |
| ::: {.line .number9 .index8 .alt2} | ::: |
| 9 | |
| ::: | ::: {.line .number8 .index7 .alt1} |
| | {.csharp .spaces}this{.csharp .keyword}.Values = {.csharp .plain}new{.csharp |
| ::: {.line .number10 .index9 .alt1} | .keyword} string{.csharp .keyword}[] { value };{.csharp .plain} |
| 10 | ::: |
| ::: | |
| | ::: {.line .number9 .index8 .alt2} |
| ::: {.line .number11 .index10 .alt2} | {.csharp .spaces}}{.csharp .plain} |
| 11 | ::: |
| ::: | |
| | ::: {.line .number10 .index9 .alt1} |
| ::: {.line .number12 .index11 .alt1} | |
| 12 | ::: |
| ::: | |
| | ::: {.line .number11 .index10 .alt2} |
| ::: {.line .number13 .index12 .alt2} | {.csharp .spaces}public{.csharp .keyword} DomainAttribute({.csharp |
| 13 | .plain}params{.csharp .keyword} string{.csharp .keyword}[] values){.csharp .plain} |
| ::: | ::: |
| | |
| ::: {.line .number14 .index13 .alt1} | ::: {.line .number12 .index11 .alt1} |
| 14 | {.csharp .spaces}{{.csharp .plain} |
| ::: | ::: |
| | |
| ::: {.line .number15 .index14 .alt2} | ::: {.line .number13 .index12 .alt2} |
| 15 | {.csharp .spaces}this{.csharp .keyword}.Values = values;{.csharp .plain} |
| ::: | ::: |
| | |
| ::: {.line .number16 .index15 .alt1} | ::: {.line .number14 .index13 .alt1} |
| 16 | {.csharp .spaces}}{.csharp .plain} |
| ::: | ::: |
| | |
| ::: {.line .number17 .index16 .alt2} | ::: {.line .number15 .index14 .alt2} |
| 17 | |
| ::: | ::: |
| | |
| ::: {.line .number18 .index17 .alt1} | ::: {.line .number16 .index15 .alt1} |
| 18 | {.csharp .spaces}public{.csharp .keyword} override{.csharp .keyword} bool{.csharp |
| ::: | .keyword} IsValid({.csharp .plain}object{.csharp .keyword} value){.csharp .plain} |
| | ::: |
| ::: {.line .number19 .index18 .alt2} | |
| 19 | ::: {.line .number17 .index16 .alt2} |
| ::: | {.csharp .spaces}{{.csharp .plain} |
| | ::: |
| ::: {.line .number20 .index19 .alt1} | |
| 20 | ::: {.line .number18 .index17 .alt1} |
| ::: | {.csharp .spaces}if{.csharp .keyword} ({.csharp .plain}null{.csharp |
| | .keyword} == value){.csharp .plain} |
| ::: {.line .number21 .index20 .alt2} | ::: |
| 21 | |
| ::: | ::: {.line .number19 .index18 .alt2} |
| | {.csharp .spaces}{{.csharp .plain} |
| ::: {.line .number22 .index21 .alt1} | ::: |
| 22 | |
| ::: | ::: {.line .number20 .index19 .alt1} |
| | {.csharp .spaces}return{.csharp .keyword} true{.csharp .keyword};{.csharp |
| ::: {.line .number23 .index22 .alt2} | .plain} |
| 23 | ::: |
| ::: | |
| | ::: {.line .number21 .index20 .alt2} |
| ::: {.line .number24 .index23 .alt1} | {.csharp .spaces}}{.csharp .plain} |
| 24 | ::: |
| ::: | |
| | ::: {.line .number22 .index21 .alt1} |
| ::: {.line .number25 .index24 .alt2} | {.csharp .spaces}return{.csharp .keyword} this{.csharp |
| 25 | .keyword}.Values.Any(item => value.ToString() == item);{.csharp .plain} |
| ::: | ::: |
| | |
| ::: {.line .number26 .index25 .alt1} | ::: {.line .number23 .index22 .alt2} |
| 26 | {.csharp .spaces}}{.csharp .plain} |
| ::: | ::: |
| | |
| ::: {.line .number27 .index26 .alt2} | ::: {.line .number24 .index23 .alt1} |
| 27 | |
| ::: | ::: |
| | |
| ::: {.line .number28 .index27 .alt1} | ::: {.line .number25 .index24 .alt2} |
| 28 | {.csharp .spaces}public{.csharp .keyword} override{.csharp .keyword} string{.csharp |
| ::: | .keyword} FormatErrorMessage({.csharp .plain}string{.csharp .keyword} name){.csharp |
| | .plain} |
| ::: {.line .number29 .index28 .alt2} | ::: |
| 29 | |
| ::: | ::: {.line .number26 .index25 .alt1} |
| | {.csharp .spaces}{{.csharp .plain} |
| ::: {.line .number30 .index29 .alt1} | ::: |
| 30 | |
| ::: | ::: {.line .number27 .index26 .alt2} |
| | {.csharp .spaces}string{.csharp .keyword}[] values = {.csharp |
| | .plain}this{.csharp .keyword}.Values.Select(value => {.csharp .plain}string{.csharp |
| | .keyword}.Format({.csharp .plain}"'{0}'"{.csharp .string}, value)).ToArray();{.csharp |
| | .plain} |
| | ::: |
| | |
| | ::: {.line .number28 .index27 .alt1} |
| | {.csharp .spaces}return{.csharp .keyword} string{.csharp |
| | .keyword}.Format({.csharp .plain}base{.csharp .keyword}.ErrorMessageString, name,{.csharp |
| | .plain}string{.csharp .keyword}.Join({.csharp .plain}","{.csharp |
| | .string}, values));{.csharp .plain} |
| | ::: |
| | |
| | ::: {.line .number29 .index28 .alt2} |
| | {.csharp .spaces}}{.csharp .plain} |
| | ::: |
| | |
| | ::: {.line .number30 .index29 .alt1} |
| | }{.csharp .plain} |
| | ::: |
| | ::::::::::::::::::::::::::::::::: |
+--------------------------------------+--------------------------------------------------------------------------------------------------+
::::
由于ASP.NET MVC在进行参数绑定的时候会自动提取应用在目标参数类型或者数据成员上的ValidationAttribute特性，并利用它们对提供的数据实施验证，所以我们不再需要像上面演示的实例一样自行在Action方法中实施验证，而只需要在定义参数类型Person的时候应用相应的ValidationAttribute特性将采用的验证规则与对应的数据成员相关联。
如下所示的是属性成员上应用了相关ValidationAttribute特性的Person类型的定义。我们在三个属性上均应用了RequiredAttribute特性将它们定义成必需的数据成员，Gender和Age属性上则分别应用了DomainAttribute和RangeAttribute特性对有效属性值的范围作了相应限制。
:::: {#highlighter_210454 .syntaxhighlighter .csharp} ::: toolbar :::
+--------------------------------------+--------------------------------------------------------------+
| ::: {.line .number1 .index0 .alt2} | ::::::::::::::::::: container |
| 1 | ::: {.line .number1 .index0 .alt2} |
| ::: | public{.csharp .keyword} class{.csharp |
| | .keyword} Person{.csharp .plain} |
| ::: {.line .number2 .index1 .alt1} | ::: |
| 2 | |
| ::: | ::: {.line .number2 .index1 .alt1} |
| | {{.csharp .plain} |
| ::: {.line .number3 .index2 .alt2} | ::: |
| 3 | |
| ::: | ::: {.line .number3 .index2 .alt2} |
| | {.csharp .spaces}[DisplayName({.csharp |
| ::: {.line .number4 .index3 .alt1} | .plain}"姓名"{.csharp .string})]{.csharp .plain} |
| 4 | ::: |
| ::: | |
| | ::: {.line .number4 .index3 .alt1} |
| ::: {.line .number5 .index4 .alt2} | {.csharp |
| 5 | .spaces}[Required(ErrorMessageResourceName = {.csharp |
| ::: | .plain}"Required"{.csharp |
| | .string}, ErrorMessageResourceType = {.csharp |
| ::: {.line .number6 .index5 .alt1} | .plain}typeof{.csharp .keyword}(resources))]{.csharp |
| 6 | .plain} |
| ::: | ::: |
| | |
| ::: {.line .number7 .index6 .alt2} | ::: {.line .number5 .index4 .alt2} |
| 7 | {.csharp .spaces}public{.csharp |
| ::: | .keyword} string{.csharp .keyword} Name { {.csharp |
| | .plain}get{.csharp .keyword}; {.csharp |
| ::: {.line .number8 .index7 .alt1} | .plain}set{.csharp .keyword}; }{.csharp .plain} |
| 8 | ::: |
| ::: | |
| | ::: {.line .number6 .index5 .alt1} |
| ::: {.line .number9 .index8 .alt2} | |
| 9 | ::: |
| ::: | |
| | ::: {.line .number7 .index6 .alt2} |
| ::: {.line .number10 .index9 .alt1} | {.csharp .spaces}[DisplayName({.csharp |
| 10 | .plain}"性别"{.csharp .string})]{.csharp .plain} |
| ::: | ::: |
| | |
| ::: {.line .number11 .index10 .alt2} | ::: {.line .number8 .index7 .alt1} |
| 11 | {.csharp |
| ::: | .spaces}[Required(ErrorMessageResourceName = {.csharp |
| | .plain}"Required"{.csharp |
| ::: {.line .number12 .index11 .alt1} | .string}, ErrorMessageResourceType = {.csharp |
| 12 | .plain}typeof{.csharp .keyword}(resources))]{.csharp |
| ::: | .plain} |
| | ::: |
| ::: {.line .number13 .index12 .alt2} | |
| 13 | ::: {.line .number9 .index8 .alt2} |
| ::: | {.csharp .spaces}[Domain({.csharp |
| | .plain}"M"{.csharp .string}, {.csharp |
| ::: {.line .number14 .index13 .alt1} | .plain}"F"{.csharp .string}, {.csharp |
| 14 | .plain}"m"{.csharp .string}, {.csharp |
| ::: | .plain}"f"{.csharp |
| | .string}, ErrorMessageResourceName = {.csharp |
| ::: {.line .number15 .index14 .alt2} | .plain}"Domain"{.csharp |
| 15 | .string}, ErrorMessageResourceType = {.csharp |
| ::: | .plain}typeof{.csharp .keyword}(resources))]{.csharp |
| | .plain} |
| ::: {.line .number16 .index15 .alt1} | ::: |
| 16 | |
| ::: | ::: {.line .number10 .index9 .alt1} |
| | {.csharp .spaces}public{.csharp |
| | .keyword} string{.csharp .keyword} Gender { {.csharp |
| | .plain}get{.csharp .keyword}; {.csharp |
| | .plain}set{.csharp .keyword}; }{.csharp .plain} |
| | ::: |
| | |
| | ::: {.line .number11 .index10 .alt2} |
| | |
| | ::: |
| | |
| | ::: {.line .number12 .index11 .alt1} |
| | {.csharp .spaces}[DisplayName({.csharp |
| | .plain}"年龄"{.csharp .string})]{.csharp .plain} |
| | ::: |
| | |
| | ::: {.line .number13 .index12 .alt2} |
| | {.csharp |
| | .spaces}[Required(ErrorMessageResourceName = {.csharp |
| | .plain}"Required"{.csharp |
| | .string}, ErrorMessageResourceType = {.csharp |
| | .plain}typeof{.csharp .keyword}(resources))]{.csharp |
| | .plain} |
| | ::: |
| | |
| | ::: {.line .number14 .index13 .alt1} |
| | {.csharp |
| | .spaces}[Range(18, 25, ErrorMessageResourceName = {.csharp |
| | .plain}"Range"{.csharp |
| | .string}, ErrorMessageResourceType = {.csharp |
| | .plain}typeof{.csharp .keyword}(resources))]{.csharp |
| | .plain} |
| | ::: |
| | |
| | ::: {.line .number15 .index14 .alt2} |
| | {.csharp .spaces}public{.csharp |
| | .keyword} int{.csharp .keyword}? Age { {.csharp |
| | .plain}get{.csharp .keyword}; {.csharp |
| | .plain}set{.csharp .keyword}; }{.csharp .plain} |
| | ::: |
| | |
| | ::: {.line .number16 .index15 .alt1} |
| | }{.csharp .plain} |
| | ::: |
| | ::::::::::::::::::: |
+--------------------------------------+--------------------------------------------------------------+
::::
::: {#scid:8747F07C-CDE8-481f-B0DF-C6CFD074BF67:7514dcd5-ebfe-4b6b-8c65-a81bf0614f1f .wlWriterEditableSmartContent}
三个ValidationAttribute特性采用的错误消息均定义在项目默认的资源文件中（我们可以采用这样的步骤创建这个资源文件：右键选择Solution Exploror中的项目，并在上下文菜单中选择"属性"选项打开"项目属性"对象框。最后在对话框中选择"资源"Tab页面，通过点击页面中的链接创建一个资源文件），具体定义如图2所示。
由于ASP.NET MVC会自动提取应用在绑定参数类型上的ValidationAttribute特性对绑定的参数实施自动化验证，所以我们根本不需要在具体的Action方法中来对参数作手工验证。如下面的代码片断所示，我们在Action方法Index中不再显式调用Validate方法，但是运行该程序并在输入不合法数据的情况下提交表单后依然会得到如图1所示的输出结果。
:::: {#highlighter_261272 .syntaxhighlighter .csharp} ::: toolbar :::
+--------------------------------------+-------------------------------------------------------+
| ::: {.line .number1 .index0 .alt2} | ::::::::::::::::::: container |
| 1 | ::: {.line .number1 .index0 .alt2} |
| ::: | public{.csharp .keyword} class{.csharp |
| | .keyword} HomeController : Controller{.csharp |
| ::: {.line .number2 .index1 .alt1} | .plain} |
| 2 | ::: |
| ::: | |
| | ::: {.line .number2 .index1 .alt1} |
| ::: {.line .number3 .index2 .alt2} | {{.csharp .plain} |
| 3 | ::: |
| ::: | |
| | ::: {.line .number3 .index2 .alt2} |
| ::: {.line .number4 .index3 .alt1} | {.csharp .spaces}//其他成员{.csharp |
| 4 | .comments} |
| ::: | ::: |
| | |
| ::: {.line .number5 .index4 .alt2} | ::: {.line .number4 .index3 .alt1} |
| 5 | {.csharp .spaces}[HttpPost]{.csharp .plain} |
| ::: | ::: |
| | |
| ::: {.line .number6 .index5 .alt1} | ::: {.line .number5 .index4 .alt2} |
| 6 | {.csharp .spaces}public{.csharp |
| ::: | .keyword} ActionResult Index(Person person){.csharp |
| | .plain} |
| ::: {.line .number7 .index6 .alt2} | ::: |
| 7 | |
| ::: | ::: {.line .number6 .index5 .alt1} |
| | {.csharp .spaces}{{.csharp .plain} |
| ::: {.line .number8 .index7 .alt1} | ::: |
| 8 | |
| ::: | ::: {.line .number7 .index6 .alt2} |
| | {.csharp .spaces}if{.csharp |
| ::: {.line .number9 .index8 .alt2} | .keyword} (!ModelState.IsValid){.csharp .plain} |
| 9 | ::: |
| ::: | |
| | ::: {.line .number8 .index7 .alt1} |
| ::: {.line .number10 .index9 .alt1} | {.csharp .spaces}{{.csharp .plain} |
| 10 | ::: |
| ::: | |
| | ::: {.line .number9 .index8 .alt2} |
| ::: {.line .number11 .index10 .alt2} | {.csharp .spaces}return{.csharp |
| 11 | .keyword} View(person);{.csharp .plain} |
| ::: | ::: |
| | |
| ::: {.line .number12 .index11 .alt1} | ::: {.line .number10 .index9 .alt1} |
| 12 | {.csharp .spaces}}{.csharp .plain} |
| ::: | ::: |
| | |
| ::: {.line .number13 .index12 .alt2} | ::: {.line .number11 .index10 .alt2} |
| 13 | {.csharp .spaces}else{.csharp .keyword} |
| ::: | ::: |
| | |
| ::: {.line .number14 .index13 .alt1} | ::: {.line .number12 .index11 .alt1} |
| 14 | {.csharp .spaces}{{.csharp .plain} |
| ::: | ::: |
| | |
| ::: {.line .number15 .index14 .alt2} | ::: {.line .number13 .index12 .alt2} |
| 15 | {.csharp .spaces}return{.csharp |
| ::: | .keyword} Content({.csharp |
| | .plain}"输入数据通过验证"{.csharp |
| ::: {.line .number16 .index15 .alt1} | .string});{.csharp .plain} |
| 16 | ::: |
| ::: | |
| | ::: {.line .number14 .index13 .alt1} |
| | {.csharp .spaces}}{.csharp .plain} |
| | ::: |
| | |
| | ::: {.line .number15 .index14 .alt2} |
| | {.csharp .spaces}}{.csharp .plain} |
| | ::: |
| | |
| | ::: {.line .number16 .index15 .alt1} |
| | }{.csharp .plain} |
| | ::: |
| | ::::::::::::::::::: |
+--------------------------------------+-------------------------------------------------------+
::::
三、让数据类型实现IValidatableObject接口
除了将验证规则通过ValidationAttribute特性直接定义在数据类型上并让ASP.NET MVC在进行参数绑定过程中据此来验证参数之外，我们还可以将验证操作直接定义在数据类型中。既然我们将验证操作直接实现在了数据类型上，意味着对应的数据对象具有"自我验证"的能力，我们姑且将这些数据类型称为"自我验证类型"。这些自我验证类型是实现了具有如下定义的接口IValidatableObject，该接口定义在"System.ComponentModel.DataAnnotations"命名空间下。
:::: {#highlighter_302301 .syntaxhighlighter .csharp} ::: toolbar :::
+------------------------------------+--------------------------------------------------------------------------------------------------+
| ::: {.line .number1 .index0 .alt2} | ::::::: container |
| 1 | ::: {.line .number1 .index0 .alt2} |
| ::: | public{.csharp .keyword} interface{.csharp .keyword} IValidatableObject{.csharp .plain} |
| | ::: |
| ::: {.line .number2 .index1 .alt1} | |
| 2 | ::: {.line .number2 .index1 .alt1} |
| ::: | {{.csharp .plain} |
| | ::: |
| ::: {.line .number3 .index2 .alt2} | |
| 3 | ::: {.line .number3 .index2 .alt2} |
| ::: | {.csharp |
| | .spaces}IEnumerable<ValidationResult> Validate( ValidationContext validationContext);{.csharp |
| ::: {.line .number4 .index3 .alt1} | .plain} |
| 4 | ::: |
| ::: | |
| | ::: {.line .number4 .index3 .alt1} |
| | }{.csharp .plain} |
| | ::: |
| | ::::::: |
+------------------------------------+--------------------------------------------------------------------------------------------------+
::::
如上面的代码片断所示，IValidatableObject接口具有唯一的方法Validate，针对自身的验证就实现在该方法中。对于上面演示实例中定义的数据类型Person，我们可以按照如下的形式将它定义成自我验证类型。
:::: {#highlighter_393067 .syntaxhighlighter .csharp} ::: toolbar :::
+--------------------------------------+--------------------------------------------------------------------------------------------------+
| ::: {.line .number1 .index0 .alt2} | ::::::::::::::::::::::::::::::::::::::::::::: container |
| 1 | ::: {.line .number1 .index0 .alt2} |
| ::: | public{.csharp .keyword} class{.csharp .keyword} Person: IValidatableObject{.csharp |
| | .plain} |
| ::: {.line .number2 .index1 .alt1} | ::: |
| 2 | |
| ::: | ::: {.line .number2 .index1 .alt1} |
| | {{.csharp .plain} |
| ::: {.line .number3 .index2 .alt2} | ::: |
| 3 | |
| ::: | ::: {.line .number3 .index2 .alt2} |
| | {.csharp .spaces}[DisplayName({.csharp .plain}"姓名"{.csharp .string})]{.csharp |
| ::: {.line .number4 .index3 .alt1} | .plain} |
| 4 | ::: |
| ::: | |
| | ::: {.line .number4 .index3 .alt1} |
| ::: {.line .number5 .index4 .alt2} | {.csharp .spaces}public{.csharp .keyword} string{.csharp .keyword} Name { {.csharp |
| 5 | .plain}get{.csharp .keyword}; {.csharp .plain}set{.csharp .keyword}; }{.csharp .plain} |
| ::: | ::: |
| | |
| ::: {.line .number6 .index5 .alt1} | ::: {.line .number5 .index4 .alt2} |
| 6 | |
| ::: | ::: |
| | |
| ::: {.line .number7 .index6 .alt2} | ::: {.line .number6 .index5 .alt1} |
| 7 | {.csharp .spaces}[DisplayName({.csharp .plain}"性别"{.csharp .string})]{.csharp |
| ::: | .plain} |
| | ::: |
| ::: {.line .number8 .index7 .alt1} | |
| 8 | ::: {.line .number7 .index6 .alt2} |
| ::: | {.csharp .spaces}public{.csharp .keyword} string{.csharp .keyword} Gender { {.csharp |
| | .plain}get{.csharp .keyword}; {.csharp .plain}set{.csharp .keyword}; }{.csharp .plain} |
| ::: {.line .number9 .index8 .alt2} | ::: |
| 9 | |
| ::: | ::: {.line .number8 .index7 .alt1} |
| | |
| ::: {.line .number10 .index9 .alt1} | ::: |
| 10 | |
| ::: | ::: {.line .number9 .index8 .alt2} |
| | {.csharp .spaces}[DisplayName({.csharp .plain}"年龄"{.csharp .string})]{.csharp |
| ::: {.line .number11 .index10 .alt2} | .plain} |
| 11 | ::: |
| ::: | |
| | ::: {.line .number10 .index9 .alt1} |
| ::: {.line .number12 .index11 .alt1} | {.csharp .spaces}public{.csharp .keyword} int{.csharp .keyword}? Age { {.csharp |
| 12 | .plain}get{.csharp .keyword}; {.csharp .plain}set{.csharp .keyword}; }{.csharp .plain} |
| ::: | ::: |
| | |
| ::: {.line .number13 .index12 .alt2} | ::: {.line .number11 .index10 .alt2} |
| 13 | |
| ::: | ::: |
| | |
| ::: {.line .number14 .index13 .alt1} | ::: {.line .number12 .index11 .alt1} |
| 14 | {.csharp .spaces}public{.csharp |
| ::: | .keyword} IEnumerable<ValidationResult> Validate( ValidationContext validationContext){.csharp |
| | .plain} |
| ::: {.line .number15 .index14 .alt2} | ::: |
| 15 | |
| ::: | ::: {.line .number13 .index12 .alt2} |
| | {.csharp .spaces}{{.csharp .plain} |
| ::: {.line .number16 .index15 .alt1} | ::: |
| 16 | |
| ::: | ::: {.line .number14 .index13 .alt1} |
| | {.csharp .spaces}Person person = validationContext.ObjectInstance {.csharp |
| ::: {.line .number17 .index16 .alt2} | .plain}as{.csharp .keyword} Person;{.csharp .plain} |
| 17 | ::: |
| ::: | |
| | ::: {.line .number15 .index14 .alt2} |
| ::: {.line .number18 .index17 .alt1} | {.csharp .spaces}if{.csharp .keyword} ({.csharp .plain}null{.csharp |
| 18 | .keyword} == person){.csharp .plain} |
| ::: | ::: |
| | |
| ::: {.line .number19 .index18 .alt2} | ::: {.line .number16 .index15 .alt1} |
| 19 | {.csharp .spaces}{{.csharp .plain} |
| ::: | ::: |
| | |
| ::: {.line .number20 .index19 .alt1} | ::: {.line .number17 .index16 .alt2} |
| 20 | {.csharp .spaces}yield {.csharp .plain}break{.csharp .keyword};{.csharp |
| ::: | .plain} |
| | ::: |
| ::: {.line .number21 .index20 .alt2} | |
| 21 | ::: {.line .number18 .index17 .alt1} |
| ::: | {.csharp .spaces}}{.csharp .plain} |
| | ::: |
| ::: {.line .number22 .index21 .alt1} | |
| 22 | ::: {.line .number19 .index18 .alt2} |
| ::: | {.csharp .spaces}if{.csharp .keyword}({.csharp .plain}string{.csharp |
| | .keyword}.IsNullOrEmpty(person.Name)){.csharp .plain} |
| ::: {.line .number23 .index22 .alt2} | ::: |
| 23 | |
| ::: | ::: {.line .number20 .index19 .alt1} |
| | {.csharp .spaces}{{.csharp .plain} |
| ::: {.line .number24 .index23 .alt1} | ::: |
| 24 | |
| ::: | ::: {.line .number21 .index20 .alt2} |
| | {.csharp .spaces}yield {.csharp .plain}return{.csharp .keyword} new{.csharp |
| ::: {.line .number25 .index24 .alt2} | .keyword} ValidationResult({.csharp .plain}"'Name'是必需字段"{.csharp .string}, {.csharp |
| 25 | .plain}new{.csharp .keyword} string{.csharp .keyword}[]{{.csharp .plain}"Name"{.csharp |
| ::: | .string}});{.csharp .plain} |
| | ::: |
| ::: {.line .number26 .index25 .alt1} | |
| 26 | ::: {.line .number22 .index21 .alt1} |
| ::: | {.csharp .spaces}}{.csharp .plain} |
| | ::: |
| ::: {.line .number27 .index26 .alt2} | |
| 27 | ::: {.line .number23 .index22 .alt2} |
| ::: | |
| | ::: |
| ::: {.line .number28 .index27 .alt1} | |
| 28 | ::: {.line .number24 .index23 .alt1} |
| ::: | {.csharp .spaces}if{.csharp .keyword} ({.csharp .plain}string{.csharp |
| | .keyword}.IsNullOrEmpty(person.Gender)){.csharp .plain} |
| ::: {.line .number29 .index28 .alt2} | ::: |
| 29 | |
| ::: | ::: {.line .number25 .index24 .alt2} |
| | {.csharp .spaces}{{.csharp .plain} |
| ::: {.line .number30 .index29 .alt1} | ::: |
| 30 | |
| ::: | ::: {.line .number26 .index25 .alt1} |
| | {.csharp .spaces}yield {.csharp .plain}return{.csharp .keyword} new{.csharp |
| ::: {.line .number31 .index30 .alt2} | .keyword} ValidationResult({.csharp .plain}"'Gender'是必需字段"{.csharp .string}, {.csharp |
| 31 | .plain}new{.csharp .keyword} string{.csharp .keyword}[] { {.csharp |
| ::: | .plain}"Gender"{.csharp .string} });{.csharp .plain} |
| | ::: |
| ::: {.line .number32 .index31 .alt1} | |
| 32 | ::: {.line .number27 .index26 .alt2} |
| ::: | {.csharp .spaces}}{.csharp .plain} |
| | ::: |
| ::: {.line .number33 .index32 .alt2} | |
| 33 | ::: {.line .number28 .index27 .alt1} |
| ::: | {.csharp .spaces}else{.csharp .keyword} if{.csharp .keyword} (!{.csharp |
| | .plain}new{.csharp .keyword} string{.csharp .keyword}[]{{.csharp .plain}"M"{.csharp |
| ::: {.line .number34 .index33 .alt1} | .string},{.csharp .plain}"F"{.csharp .string}}.Any( g=>{.csharp .plain}string{.csharp |
| 34 | .keyword}.Compare(person.Gender,g, {.csharp .plain}true{.csharp .keyword}) == 0)){.csharp |
| ::: | .plain} |
| | ::: |
| ::: {.line .number35 .index34 .alt2} | |
| 35 | ::: {.line .number29 .index28 .alt2} |
| ::: | {.csharp .spaces}{{.csharp .plain} |
| | ::: |
| ::: {.line .number36 .index35 .alt1} | |
| 36 | ::: {.line .number30 .index29 .alt1} |
| ::: | {.csharp .spaces}yield {.csharp .plain}return{.csharp .keyword} new{.csharp |
| | .keyword} ValidationResult({.csharp .plain}"有效'Gender'必须是'M','F'之一"{.csharp |
| ::: {.line .number37 .index36 .alt2} | .string}, {.csharp .plain}new{.csharp .keyword} string{.csharp .keyword}[] { {.csharp |
| 37 | .plain}"Gender"{.csharp .string} });{.csharp .plain} |
| ::: | ::: |
| | |
| ::: {.line .number38 .index37 .alt1} | ::: {.line .number31 .index30 .alt2} |
| 38 | {.csharp .spaces}}{.csharp .plain} |
| ::: | ::: |
| | |
| ::: {.line .number39 .index38 .alt2} | ::: {.line .number32 .index31 .alt1} |
| 39 | |
| ::: | ::: |
| | |
| ::: {.line .number40 .index39 .alt1} | ::: {.line .number33 .index32 .alt2} |
| 40 | {.csharp .spaces}if{.csharp .keyword} ({.csharp .plain}null{.csharp |
| ::: | .keyword} == person.Age){.csharp .plain} |
| | ::: |
| ::: {.line .number41 .index40 .alt2} | |
| 41 | ::: {.line .number34 .index33 .alt1} |
| ::: | {.csharp .spaces}{{.csharp .plain} |
| | ::: |
| ::: {.line .number42 .index41 .alt1} | |
| 42 | ::: {.line .number35 .index34 .alt2} |
| ::: | {.csharp .spaces}yield {.csharp .plain}return{.csharp .keyword} new{.csharp |
| | .keyword} ValidationResult({.csharp .plain}"'Age'是必需字段"{.csharp .string}, {.csharp |
| | .plain}new{.csharp .keyword} string{.csharp .keyword}[] { {.csharp .plain}"Age"{.csharp |
| | .string} });{.csharp .plain} |
| | ::: |
| | |
| | ::: {.line .number36 .index35 .alt1} |
| | {.csharp .spaces}}{.csharp .plain} |
| | ::: |
| | |
| | ::: {.line .number37 .index36 .alt2} |
| | {.csharp .spaces}else{.csharp .keyword} if{.csharp |
| | .keyword} (person.Age > 25 || person.Age < 18){.csharp .plain} |
| | ::: |
| | |
| | ::: {.line .number38 .index37 .alt1} |
| | {.csharp .spaces}{{.csharp .plain} |
| | ::: |
| | |
| | ::: {.line .number39 .index38 .alt2} |
| | {.csharp .spaces}yield {.csharp .plain}return{.csharp .keyword} new{.csharp |
| | .keyword} ValidationResult({.csharp .plain}"'Age'必须在18到25周岁之间"{.csharp |
| | .string}, {.csharp .plain}new{.csharp .keyword} string{.csharp .keyword}[] { {.csharp |
| | .plain}"Age"{.csharp .string} });{.csharp .plain} |
| | ::: |
| | |
| | ::: {.line .number40 .index39 .alt1} |
| | {.csharp .spaces}} {.csharp .plain} |
| | ::: |
| | |
| | ::: {.line .number41 .index40 .alt2} |
| | {.csharp .spaces}}{.csharp .plain} |
| | ::: |
| | |
| | ::: {.line .number42 .index41 .alt1} |
| | }{.csharp .plain} |
| | ::: |
| | ::::::::::::::::::::::::::::::::::::::::::::: |
+--------------------------------------+--------------------------------------------------------------------------------------------------+
::::
如上面的代码片断所示，我们让Person类型实现了IValidatableObject接口。在实现的Validate方法中，我们从验证上下文中获取被验证的Person对象，并对其属性成员进行逐个验证。如果数据成员没有通过验证，我们通过一个ValidationResult对象封装错误消息和数据成员名称（属性名），该方法最终返回的是一个元素类型为ValidationResult的集合。在不对其他代码作任何改动的情况下，我们直接运行该程序并在输入不合法数据的情况下提交表单后依然会得到如图1所示的输出结果。
四、让数据类型实现IDataErrorInfo接口
上面我们让数据类型实现IValidatableObject接口并将具体的验证逻辑定义在实现的Validate方法中，这样的类型能够被ASP.NET MVC所识别，后者会自动调用该方法对绑定的数据对象实施验证。如果我们让数据类型实现IDataErrorInfo接口也能实现类似的自动化验证效果。
IDataErrorInfo接口定义在"System.ComponentModel"命名空间下，它提供了一种标准的错误信息定制方式。如下面的代码片段所示，IDataErrorInfo具有两个成员，只读属性Error用于获取基于自身的错误消息，而只读索引用于返回指定数据成员的错误消息。
:::: {#highlighter_197344 .syntaxhighlighter .csharp} ::: toolbar :::
+------------------------------------+------------------------------------+
| ::: {.line .number1 .index0 .alt2} | :::::::: container |
| 1 | ::: {.line .number1 .index0 .alt2} |
| ::: | public{.csharp |
| | .keyword} interface{.csharp |
| ::: {.line .number2 .index1 .alt1} | .keyword} IDataErrorInfo{.csharp |
| 2 | .plain} |
| ::: | ::: |
| | |
| ::: {.line .number3 .index2 .alt2} | ::: {.line .number2 .index1 .alt1} |
| 3 | {{.csharp .plain} |
| ::: | ::: |
| | |
| ::: {.line .number4 .index3 .alt1} | ::: {.line .number3 .index2 .alt2} |
| 4 | {.csharp |
| ::: | .spaces}string{.csharp |
| | .keyword} Error { {.csharp |
| ::: {.line .number5 .index4 .alt2} | .plain}get{.csharp |
| 5 | .keyword}; }{.csharp .plain} |
| ::: | ::: |
| | |
| | ::: {.line .number4 .index3 .alt1} |
| | {.csharp |
| | .spaces}string{.csharp |
| | .keyword} this{.csharp |
| | .keyword}[{.csharp |
| | .plain}string{.csharp |
| | .keyword} columnName] { {.csharp |
| | .plain}get{.csharp |
| | .keyword}; }{.csharp .plain} |
| | ::: |
| | |
| | ::: {.line .number5 .index4 .alt2} |
| | }{.csharp .plain} |
| | ::: |
| | :::::::: |
+------------------------------------+------------------------------------+
::::
同样是针对上面演示的实例，现在我们对需要被验证的数据类型Person进行了重新定义。如下面的代码片断所示，我们让Person实现了IDataErrorInfo接口。在实现的索引中，我们将索引参数columnName视为属性名称，根据它按照上面的规则对相应的属性成员实施验证，并在验证失败的情况下返回相应的错误消息。在不对其他代码作任何改动的情况下，我们直接运行该程序并在输入不合法数据的情况下提交表单后依然会得到如图1所示的输出结果。
:::: {#highlighter_511172 .syntaxhighlighter .csharp} ::: toolbar :::
+--------------------------------------+--------------------------------------------------------------------------+
| ::: {.line .number1 .index0 .alt2} | :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: container |
| 1 | ::: {.line .number1 .index0 .alt2} |
| ::: | public{.csharp .keyword} class{.csharp |
| | .keyword} Person : IDataErrorInfo{.csharp .plain} |
| ::: {.line .number2 .index1 .alt1} | ::: |
| 2 | |
| ::: | ::: {.line .number2 .index1 .alt1} |
| | {{.csharp .plain} |
| ::: {.line .number3 .index2 .alt2} | ::: |
| 3 | |
| ::: | ::: {.line .number3 .index2 .alt2} |
| | {.csharp .spaces}[DisplayName({.csharp .plain}"姓名"{.csharp |
| ::: {.line .number4 .index3 .alt1} | .string})]{.csharp .plain} |
| 4 | ::: |
| ::: | |
| | ::: {.line .number4 .index3 .alt1} |
| ::: {.line .number5 .index4 .alt2} | {.csharp .spaces}public{.csharp .keyword} string{.csharp |
| 5 | .keyword} Name { {.csharp .plain}get{.csharp .keyword}; {.csharp |
| ::: | .plain}set{.csharp .keyword}; }{.csharp .plain} |
| | ::: |
| ::: {.line .number6 .index5 .alt1} | |
| 6 | ::: {.line .number5 .index4 .alt2} |
| ::: | |
| | ::: |
| ::: {.line .number7 .index6 .alt2} | |
| 7 | ::: {.line .number6 .index5 .alt1} |
| ::: | {.csharp .spaces}[DisplayName({.csharp .plain}"性别"{.csharp |
| | .string})]{.csharp .plain} |
| ::: {.line .number8 .index7 .alt1} | ::: |
| 8 | |
| ::: | ::: {.line .number7 .index6 .alt2} |
| | {.csharp .spaces}public{.csharp .keyword} string{.csharp |
| ::: {.line .number9 .index8 .alt2} | .keyword} Gender { {.csharp .plain}get{.csharp .keyword}; {.csharp |
| 9 | .plain}set{.csharp .keyword}; }{.csharp .plain} |
| ::: | ::: |
| | |
| ::: {.line .number10 .index9 .alt1} | ::: {.line .number8 .index7 .alt1} |
| 10 | |
| ::: | ::: |
| | |
| ::: {.line .number11 .index10 .alt2} | ::: {.line .number9 .index8 .alt2} |
| 11 | {.csharp .spaces}[DisplayName({.csharp .plain}"年龄"{.csharp |
| ::: | .string})]{.csharp .plain} |
| | ::: |
| ::: {.line .number12 .index11 .alt1} | |
| 12 | ::: {.line .number10 .index9 .alt1} |
| ::: | {.csharp .spaces}public{.csharp .keyword} int{.csharp |
| | .keyword}? Age { {.csharp .plain}get{.csharp .keyword}; {.csharp |
| ::: {.line .number13 .index12 .alt2} | .plain}set{.csharp .keyword}; }{.csharp .plain} |
| 13 | ::: |
| ::: | |
| | ::: {.line .number11 .index10 .alt2} |
| ::: {.line .number14 .index13 .alt1} | |
| 14 | ::: |
| ::: | |
| | ::: {.line .number12 .index11 .alt1} |
| ::: {.line .number15 .index14 .alt2} | {.csharp .spaces}[ScaffoldColumn({.csharp .plain}false{.csharp |
| 15 | .keyword})]{.csharp .plain} |
| ::: | ::: |
| | |
| ::: {.line .number16 .index15 .alt1} | ::: {.line .number13 .index12 .alt2} |
| 16 | {.csharp .spaces}public{.csharp .keyword} string{.csharp |
| ::: | .keyword} Error { {.csharp .plain}get{.csharp .keyword}; {.csharp |
| | .plain}private{.csharp .keyword} set{.csharp .keyword}; }{.csharp |
| ::: {.line .number17 .index16 .alt2} | .plain} |
| 17 | ::: |
| ::: | |
| | ::: {.line .number14 .index13 .alt1} |
| ::: {.line .number18 .index17 .alt1} | |
| 18 | ::: |
| ::: | |
| | ::: {.line .number15 .index14 .alt2} |
| ::: {.line .number19 .index18 .alt2} | {.csharp .spaces}public{.csharp .keyword} string{.csharp |
| 19 | .keyword} this{.csharp .keyword}[{.csharp .plain}string{.csharp |
| ::: | .keyword} columnName]{.csharp .plain} |
| | ::: |
| ::: {.line .number20 .index19 .alt1} | |
| 20 | ::: {.line .number16 .index15 .alt1} |
| ::: | {.csharp .spaces}{{.csharp .plain} |
| | ::: |
| ::: {.line .number21 .index20 .alt2} | |
| 21 | ::: {.line .number17 .index16 .alt2} |
| ::: | {.csharp .spaces}get{.csharp .keyword} |
| | ::: |
| ::: {.line .number22 .index21 .alt1} | |
| 22 | ::: {.line .number18 .index17 .alt1} |
| ::: | {.csharp .spaces}{{.csharp .plain} |
| | ::: |
| ::: {.line .number23 .index22 .alt2} | |
| 23 | ::: {.line .number19 .index18 .alt2} |
| ::: | {.csharp .spaces}switch{.csharp |
| | .keyword} (columnName){.csharp .plain} |
| ::: {.line .number24 .index23 .alt1} | ::: |
| 24 | |
| ::: | ::: {.line .number20 .index19 .alt1} |
| | {.csharp .spaces}{{.csharp .plain} |
| ::: {.line .number25 .index24 .alt2} | ::: |
| 25 | |
| ::: | ::: {.line .number21 .index20 .alt2} |
| | {.csharp .spaces}case{.csharp |
| ::: {.line .number26 .index25 .alt1} | .keyword} "Name"{.csharp .string}:{.csharp .plain} |
| 26 | ::: |
| ::: | |
| | ::: {.line .number22 .index21 .alt1} |
| ::: {.line .number27 .index26 .alt2} | {.csharp .spaces}{ {.csharp .plain} |
| 27 | ::: |
| ::: | |
| | ::: {.line .number23 .index22 .alt2} |
| ::: {.line .number28 .index27 .alt1} | {.csharp .spaces}if{.csharp |
| 28 | .keyword}({.csharp .plain}string{.csharp |
| ::: | .keyword}.IsNullOrEmpty({.csharp .plain}this{.csharp |
| | .keyword}.Name)){.csharp .plain} |
| ::: {.line .number29 .index28 .alt2} | ::: |
| 29 | |
| ::: | ::: {.line .number24 .index23 .alt1} |
| | {.csharp .spaces}{{.csharp .plain} |
| ::: {.line .number30 .index29 .alt1} | ::: |
| 30 | |
| ::: | ::: {.line .number25 .index24 .alt2} |
| | {.csharp .spaces}return{.csharp |
| ::: {.line .number31 .index30 .alt2} | .keyword} "'姓名'是必需字段"{.csharp .string};{.csharp .plain} |
| 31 | ::: |
| ::: | |
| | ::: {.line .number26 .index25 .alt1} |
| ::: {.line .number32 .index31 .alt1} | {.csharp .spaces}}{.csharp .plain} |
| 32 | ::: |
| ::: | |
| | ::: {.line .number27 .index26 .alt2} |
| ::: {.line .number33 .index32 .alt2} | {.csharp .spaces}return{.csharp |
| 33 | .keyword} null{.csharp .keyword};{.csharp .plain} |
| ::: | ::: |
| | |
| ::: {.line .number34 .index33 .alt1} | ::: {.line .number28 .index27 .alt1} |
| 34 | {.csharp .spaces}}{.csharp .plain} |
| ::: | ::: |
| | |
| ::: {.line .number35 .index34 .alt2} | ::: {.line .number29 .index28 .alt2} |
| 35 | {.csharp .spaces}case{.csharp |
| ::: | .keyword} "Gender"{.csharp .string}:{.csharp .plain} |
| | ::: |
| ::: {.line .number36 .index35 .alt1} | |
| 36 | ::: {.line .number30 .index29 .alt1} |
| ::: | {.csharp .spaces}{{.csharp .plain} |
| | ::: |
| ::: {.line .number37 .index36 .alt2} | |
| 37 | ::: {.line .number31 .index30 .alt2} |
| ::: | {.csharp .spaces}if{.csharp |
| | .keyword} ({.csharp .plain}string{.csharp |
| ::: {.line .number38 .index37 .alt1} | .keyword}.IsNullOrEmpty({.csharp .plain}this{.csharp |
| 38 | .keyword}.Gender)){.csharp .plain} |
| ::: | ::: |
| | |
| ::: {.line .number39 .index38 .alt2} | ::: {.line .number32 .index31 .alt1} |
| 39 | {.csharp .spaces}{{.csharp .plain} |
| ::: | ::: |
| | |
| ::: {.line .number40 .index39 .alt1} | ::: {.line .number33 .index32 .alt2} |
| 40 | {.csharp .spaces}return{.csharp |
| ::: | .keyword} "'性别'是必需字段"{.csharp .string};{.csharp .plain} |
| | ::: |
| ::: {.line .number41 .index40 .alt2} | |
| 41 | ::: {.line .number34 .index33 .alt1} |
| ::: | {.csharp .spaces}}{.csharp .plain} |
| | ::: |
| ::: {.line .number42 .index41 .alt1} | |
| 42 | ::: {.line .number35 .index34 .alt2} |
| ::: | {.csharp .spaces}else{.csharp |
| | .keyword} if{.csharp .keyword} (!{.csharp .plain}new{.csharp |
| ::: {.line .number43 .index42 .alt2} | .keyword} string{.csharp .keyword}[] { {.csharp .plain}"M"{.csharp |
| 43 | .string}, {.csharp .plain}"F"{.csharp .string} }.Any({.csharp |
| ::: | .plain} |
| | ::: |
| ::: {.line .number44 .index43 .alt1} | |
| 44 | ::: {.line .number36 .index35 .alt1} |
| ::: | {.csharp .spaces}g => {.csharp |
| | .plain}string{.csharp .keyword}.Compare({.csharp |
| ::: {.line .number45 .index44 .alt2} | .plain}this{.csharp .keyword}.Gender, g, {.csharp |
| 45 | .plain}true{.csharp .keyword}) == 0)){.csharp .plain} |
| ::: | ::: |
| | |
| ::: {.line .number46 .index45 .alt1} | ::: {.line .number37 .index36 .alt2} |
| 46 | {.csharp .spaces}{{.csharp .plain} |
| ::: | ::: |
| | |
| ::: {.line .number47 .index46 .alt2} | ::: {.line .number38 .index37 .alt1} |
| 47 | {.csharp .spaces}return{.csharp |
| ::: | .keyword} "'性别'必须是'M','F'之一"{.csharp .string};{.csharp |
| | .plain} |
| ::: {.line .number48 .index47 .alt1} | ::: |
| 48 | |
| ::: | ::: {.line .number39 .index38 .alt2} |
| | {.csharp .spaces}}{.csharp .plain} |
| ::: {.line .number49 .index48 .alt2} | ::: |
| 49 | |
| ::: | ::: {.line .number40 .index39 .alt1} |
| | {.csharp .spaces}return{.csharp |
| ::: {.line .number50 .index49 .alt1} | .keyword} null{.csharp .keyword};{.csharp .plain} |
| 50 | ::: |
| ::: | |
| | ::: {.line .number41 .index40 .alt2} |
| ::: {.line .number51 .index50 .alt2} | {.csharp .spaces}}{.csharp .plain} |
| 51 | ::: |
| ::: | |
| | ::: {.line .number42 .index41 .alt1} |
| ::: {.line .number52 .index51 .alt1} | {.csharp .spaces}case{.csharp |
| 52 | .keyword} "Age"{.csharp .string}:{.csharp .plain} |
| ::: | ::: |
| | |
| ::: {.line .number53 .index52 .alt2} | ::: {.line .number43 .index42 .alt2} |
| 53 | {.csharp .spaces}{{.csharp .plain} |
| ::: | ::: |
| | |
| ::: {.line .number54 .index53 .alt1} | ::: {.line .number44 .index43 .alt1} |
| 54 | {.csharp .spaces}if{.csharp |
| ::: | .keyword} ({.csharp .plain}null{.csharp .keyword} == {.csharp |
| | .plain}this{.csharp .keyword}.Age){.csharp .plain} |
| ::: {.line .number55 .index54 .alt2} | ::: |
| 55 | |
| ::: | ::: {.line .number45 .index44 .alt2} |
| | {.csharp .spaces}{{.csharp .plain} |
| ::: {.line .number56 .index55 .alt1} | ::: |
| 56 | |
| ::: | ::: {.line .number46 .index45 .alt1} |
| | {.csharp .spaces}return{.csharp |
| ::: {.line .number57 .index56 .alt2} | .keyword} "'年龄'是必需字段"{.csharp .string};{.csharp .plain} |
| 57 | ::: |
| ::: | |
| | ::: {.line .number47 .index46 .alt2} |
| ::: {.line .number58 .index57 .alt1} | {.csharp .spaces}}{.csharp .plain} |
| 58 | ::: |
| ::: | |
| | ::: {.line .number48 .index47 .alt1} |
| ::: {.line .number59 .index58 .alt2} | {.csharp .spaces}else{.csharp |
| 59 | .keyword} if{.csharp .keyword} ({.csharp .plain}this{.csharp |
| ::: | .keyword}.Age > 25 || {.csharp .plain}this{.csharp |
| | .keyword}.Age < 18){.csharp .plain} |
| | ::: |
| | |
| | ::: {.line .number49 .index48 .alt2} |
| | {.csharp .spaces}{{.csharp .plain} |
| | ::: |
| | |
| | ::: {.line .number50 .index49 .alt1} |
| | {.csharp .spaces}return{.csharp |
| | .keyword} "'年龄'必须在18到25周岁之间"{.csharp .string};{.csharp |
| | .plain} |
| | ::: |
| | |
| | ::: {.line .number51 .index50 .alt2} |
| | {.csharp .spaces}}{.csharp .plain} |
| | ::: |
| | |
| | ::: {.line .number52 .index51 .alt1} |
| | {.csharp .spaces}return{.csharp |
| | .keyword} null{.csharp .keyword};{.csharp .plain} |
| | ::: |
| | |
| | ::: {.line .number53 .index52 .alt2} |
| | {.csharp .spaces}}{.csharp .plain} |
| | ::: |
| | |
| | ::: {.line .number54 .index53 .alt1} |
| | {.csharp .spaces}default{.csharp |
| | .keyword}: {.csharp .plain}return{.csharp .keyword} null{.csharp |
| | .keyword};{.csharp .plain} |
| | ::: |
| | |
| | ::: {.line .number55 .index54 .alt2} |
| | {.csharp .spaces} |
| | ::: |
| | |
| | ::: {.line .number56 .index55 .alt1} |
| | {.csharp .spaces}}{.csharp .plain} |
| | ::: |
| | |
| | ::: {.line .number57 .index56 .alt2} |
| | {.csharp .spaces}}{.csharp .plain} |
| | ::: |
| | |
| | ::: {.line .number58 .index57 .alt1} |
| | {.csharp .spaces}}{.csharp .plain} |
| | ::: |
| | |
| | ::: {.line .number59 .index58 .alt2} |
| | }{.csharp .plain} |
| | ::: |
| | :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: |
+--------------------------------------+--------------------------------------------------------------------------+
::::
作者：Artech 出处：：http://artech.cnblogs.com/ 原文地址：：http://www.cnblogs.com/artech/p/asp-net-mvc-validation-programming.html
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