ASP.NET Core 模型绑定错误消息本地化 [英] ASP.NET Core Model Binding Error Messages Localization

问题描述

我正在使用 ASP.NET Core，并尝试本地化应用程序.我设法使用新 asp .net 核心资源来本地化控制器和视图，并使用旧 资源来本地化模型验证的错误消息.但是，当错误消息未链接到模型字段注释(如必需")并且模型绑定的数据不正确(如需要数字的文本)时，我收到如下错误，我是无法本地化:

<块引用>

值 'abc' 对 ID 无效."

当我在 View 中为 ID 属性输入 abc 时，由于无法对字段进行模型绑定并显示验证字段附近的消息，说值 'abc' 对 ID 无效.".这是我正在使用的课程:

公共类国家:IHasID{公共 int ID { 获取；放;}[必需(ErrorMessageResourceType = typeof(L.Val),ErrorMessageResourceName = "NameR")][MaxLength(100, ErrorMessageResourceType = typeof(L.Val),ErrorMessageResourceName = "Max")]公共字符串名称 { 获取；放;}/*其他一些属性*/}

我在互联网上发现的类似问题要么针对较旧的asp .net版本，要么没有帮助我解决问题.

解决方案

要自定义框架模型绑定错误消息，您需要为

我使用的键就像原始消息，除了 ValueMustNotBeNull 的键与 ValueIsInvalid 相同，所以我使用了 Null 值无效. 为它.

配置选项 - 在 ConfigureServices 方法中，添加 Mvc 时，配置其选项以设置 ModelBindingMessageProvider 的消息访问器:

public void ConfigureServices(IServiceCollection services){services.AddLocalization(options => { options.ResourcesPath = "Resources"; });services.AddMvc(options =>{var F = services.BuildServiceProvider().GetService();var L = F.Create("ModelBindingMessages", "AspNetCoreLocalizationSample");options.ModelBindingMessageProvider.ValueIsInvalidAccessor =(x) =>L["值 '{0}' 无效.", x];options.ModelBindingMessageProvider.ValueMustBeANumberAccessor =(x) =>L["字段 {0} 必须是数字.", x];options.ModelBindingMessageProvider.MissingBindRequiredValueAccessor =(x) =>L["未提供 '{0}' 属性的值.", x];options.ModelBindingMessageProvider.AttemptedValueIsInvalidAccessor =(x, y) =>L["值 '{0}' 对 {1} 无效.", x, y];options.ModelBindingMessageProvider.MissingKeyOrValueAccessor =() =>L["需要一个值."];options.ModelBindingMessageProvider.UnknownValueIsInvalidAccessor =(x) =>L["提供的值对于 {0} 无效.", x];options.ModelBindingMessageProvider.ValueMustNotBeNullAccessor =(x) =>L["空值无效.", x];}).AddDataAnnotationsLocalization().AddViewLocalization();services.Configure(options =>{var supportedCultures = new[]{new CultureInfo("en"), new CultureInfo("fa")};options.DefaultRequestCulture = new RequestCulture("en", "en");options.SupportedCultures = supportedCultures;options.SupportedUICultures = supportedCultures;});}

还要在Configure方法的开头添加这段代码:

var supportedCultures = new[] { new CultureInfo("en"), new CultureInfo("fa") };app.UseRequestLocalization(new RequestLocalizationOptions(){DefaultRequestCulture = new RequestCulture(new CultureInfo("en")),支持的文化 = 支持的文化，支持的UICultures = 支持的文化});

ASP.NET Core 2.0 的重要说明

<块引用>

在 ASP.NET Core 2.0 中，模型绑定消息提供程序属性已经获得只读，但已为每个属性添加了一个 setter 方法.

例如设置ValueIsInvalidAccessor，你应该使用 SetValueIsInvalidAccessor()这种方法:

options.ModelBindingMessageProvider.SetValueIsInvalidAccessor ((x) =>L["值 '{0}' 无效.", x]);

I'm using ASP.NET Core, and trying to localize the application. I managed to use new asp .net core resources to localize controllers and views, and old resources to localize error messages for model validation. However, when the error message is not linked to a model field annotation (like "Required") and the data for model binding is incorrect (like a text where a number is expected), I receive the error like below, which I'm unable to localize:

"The value 'abc' is not valid for ID."

When I enter abc for ID property in View, since the model binding can not be done to the field and it shows a validation message near the field, saying "The value 'abc' is not valid for ID.". Here is the class I'm using:

public class Country : IHasID
{
    public int ID { get; set; }

    [Required(ErrorMessageResourceType = typeof(L.Val),
    ErrorMessageResourceName = "NameR")]
    [MaxLength(100, ErrorMessageResourceType = typeof(L.Val), 
    ErrorMessageResourceName = "Max")]
    public string Name { get; set; }

    /*Some other properties*/
}

The similar issues I found on the internet were either targeted to older asp .net version, or else didn't help me solve the problem.

解决方案

To customize framework model binding error messages, you need to set custom accessors for different error message accessors of ModelBindingMessageProvider.

Example

Here you can download a full source code of what is described in this post. The repository contains example for ASP.NET Core 2.0 (VS 2017.3) and ASP.NET Core 1.1 (VS 2015):

• r-aghaei/AspNetCoreLocalizationSample

Also here you can see the example, live:

• aspnetcorelocalizationsample.azurewebsites.net

Default Error Messages

These are default error messages which the framework shows when model binding to a property fails:

MissingBindRequiredValueAccessor    A value for the '{0}' property was not provided.
MissingKeyOrValueAccessor           A value is required.
ValueMustNotBeNullAccessor          The value '{0}' is invalid. 
AttemptedValueIsInvalidAccessor     The value '{0}' is not valid for {1}.
UnknownValueIsInvalidAccessor       The supplied value is invalid for {0}.
ValueIsInvalidAccessor              The value '{0}' is invalid.
ValueMustBeANumberAccessor          The field {0} must be a number.

In addition to above messages, ASP.NET Core 2.0 have these messages as well:

MissingRequestBodyRequiredValueAccessor       A non-empty request body is required.
NonPropertyAttemptedValueIsInvalidAccessor    The value '{0}' is not valid.
NonPropertyUnknownValueIsInvalidAccessor      The supplied value is invalid.
NonPropertyValueMustBeANumberAccessor         The field must be a number.

Localize ASP.NET Core Model Binding Error Messages

To localize ASP.NET Core model binding error messages, follow these steps:

1. Create Resource File - Create a resource file under Resources folder in your solution and name the file ModelBindingMessages.fa.resx. The name can be anything else but we will use it to create a localizer. In the example, I used fa (Persian) culture.

2. Add Resource Keys - Open the resource file and add keys and values which you want to use for localizing error messages. I used keys and values like below image:

   Keys which I used are like original messages, except the key for ValueMustNotBeNull which was the same as ValueIsInvalid, so I used Null value is invalid. for it.

3. Configure Options - In ConfigureServices method, when adding Mvc, configure its options to set message accessors for ModelBindingMessageProvider:

   public void ConfigureServices(IServiceCollection services)
   {
       services.AddLocalization(options => { options.ResourcesPath = "Resources"; });
       services.AddMvc(options =>
       {
           var F = services.BuildServiceProvider().GetService<IStringLocalizerFactory>();
           var L = F.Create("ModelBindingMessages", "AspNetCoreLocalizationSample");
           options.ModelBindingMessageProvider.ValueIsInvalidAccessor =
               (x) => L["The value '{0}' is invalid.", x];
           options.ModelBindingMessageProvider.ValueMustBeANumberAccessor =
               (x) => L["The field {0} must be a number.", x];
           options.ModelBindingMessageProvider.MissingBindRequiredValueAccessor =
               (x) => L["A value for the '{0}' property was not provided.", x];
           options.ModelBindingMessageProvider.AttemptedValueIsInvalidAccessor =
               (x, y) => L["The value '{0}' is not valid for {1}.", x, y];
           options.ModelBindingMessageProvider.MissingKeyOrValueAccessor =
               () => L["A value is required."];
           options.ModelBindingMessageProvider.UnknownValueIsInvalidAccessor =
               (x) => L["The supplied value is invalid for {0}.", x];
           options.ModelBindingMessageProvider.ValueMustNotBeNullAccessor =
               (x) => L["Null value is invalid.", x];
       })
       .AddDataAnnotationsLocalization()
       .AddViewLocalization();
       services.Configure<RequestLocalizationOptions>(options =>
       {
           var supportedCultures = new[]{new CultureInfo("en"), new CultureInfo("fa")};
           options.DefaultRequestCulture = new RequestCulture("en", "en");
           options.SupportedCultures = supportedCultures;
           options.SupportedUICultures = supportedCultures;
       });
   }
   

   Also add this code at beginning of Configure method:

   var supportedCultures = new[] { new CultureInfo("en"), new CultureInfo("fa") };
   app.UseRequestLocalization(new RequestLocalizationOptions()
   {
       DefaultRequestCulture = new RequestCulture(new CultureInfo("en")),
       SupportedCultures = supportedCultures,
       SupportedUICultures = supportedCultures
   });
   

Important Note for ASP.NET Core 2.0

In ASP.NET Core 2.0, model binding message provider properties has got read only, but a setter method for each property has been added.

For example, to set ValueIsInvalidAccessor, you should use SetValueIsInvalidAccessor() method this way:

options.ModelBindingMessageProvider.SetValueIsInvalidAccessor (
    (x) => L["The value '{0}' is invalid.", x]);

这篇关于ASP.NET Core 模型绑定错误消息本地化的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！