ASP.NET MVC的国际化问题

在博客园里有这篇帖子讲的已经很全面了，但是我认为还不够优雅，整个看起来好混乱，像国外这位老兄的帖子处理的就很整洁，简单记录如下：

通常的国际化处理方法

public class User
{
    [Required(ErrorMessageResourceName = "Validation_Required", ErrorMessageResourceType = typeof(ModelTranslations))]
    [LocalizedDisplayNameAttribute("User_Id", NameResourceType=typeof(ModelTranslations))]
    public int Id { get; set; }
 
    [Required(ErrorMessageResourceName = "Validation_Required", ErrorMessageResourceType = typeof(ModelTranslations))]
    [StringLength(40, ErrorMessageResourceName = "Validation_StringLength", ErrorMessageResourceType = typeof(ModelTranslations))]
    [LocalizedDisplayNameAttribute("User_FirstName", NameResourceType=typeof(ModelTranslations))]
    public string FirstName { get; set; }
 
    [Required(ErrorMessageResourceName = "Validation_Required", ErrorMessageResourceType = typeof(ModelTranslations))]
    [StringLength(40, ErrorMessageResourceName = "Validation_StringLength", ErrorMessageResourceType = typeof(ModelTranslations))]
    [LocalizedDisplayNameAttribute("User_LastName", NameResourceType=typeof(ModelTranslations))]
    public string LastName { get; set; }
}

可以看出来很混乱。

public class User
{
    [Required]
    [LocalizedDisplayNameAttribute("User_Id")]
    public int Id { get; set; }
 
    [Required]
    [StringLength(40)]
    [LocalizedDisplayNameAttribute("User_FirstName")]
    public string FirstName { get; set; }
 
    [Required]
    [StringLength(40)]
    [LocalizedDisplayNameAttribute("User_LastName")]
    public string LastName { get; set; }
}

是不是整洁多了，但是这个整洁的代价就是要背后要写代码的

public class RequiredAttribute : System.ComponentModel.DataAnnotations.RequiredAttribute
{
    private string _displayName;
 
    public RequiredAttribute()
    {
        ErrorMessageResourceName = "Validation_Required";
    }
 
    protected override ValidationResult IsValid(object value, ValidationContext validationContext)
    {
        _displayName = validationContext.DisplayName;
        return base.IsValid(value, validationContext);
    }
 
    public override string FormatErrorMessage(string name)
    {
        var msg = LanguageService.Instance.Translate(ErrorMessageResourceName);
        return string.Format(msg, _displayName);
    }
}

这个是验证属性的实现代码。

ublic class LocalizedDisplayNameAttribute : DisplayNameAttribute
{
    private PropertyInfo _nameProperty;
    private Type _resourceType;
 
    public LocalizedDisplayNameAttribute(string className, string propertyName)
        : base(className + (propertyName == null ? "_Class" : ("_" + propertyName)))
    {
 
    }
 
    public override string DisplayName
    {
        get
        {
            return LanguageService.Instance.Translate(base.DisplayName) ?? "**" + base.DisplayName + "**";
        }
    }
}

这是实现DisplayName属性的实现代码

public class LanguageService
{
    private static LanguageService _instance = new LanguageService();
    private List<ResourceManager> _resourceManagers = new List<ResourceManager>();
 
    private LanguageService()
    {
    }
 
    public static LanguageService Instance { get { return _instance; } }
 
    public void Add(ResourceManager mgr)
    {
        _resourceManagers.Add(mgr);
    }
 
    public string Translate(string key)
    {
        foreach (var item in _resourceManagers)
        {
            var value = item.GetString(key);
            if (value != null)
                return value;
        }
 
        return null;
    }
}

   这是上述类依赖的管理资源的代码。

但上述的解决办法对于客户端验证还是有问题，以下是一个简单的实现

public class RequiredAttributeAdapter : DataAnnotationsModelValidator<RequiredAttribute>
{
    public RequiredAttributeAdapter(ModelMetadata metadata, ControllerContext context, RequiredAttribute attribute)
        : base(metadata, context, attribute)
    {
    }
 
    public static void SelfRegister()
    {
        DataAnnotationsModelValidatorProvider
            .RegisterAdapter(
                typeof (RequiredAttribute),
                typeof (RequiredAttributeAdapter));
    }
 
    public override IEnumerable<ModelClientValidationRule> GetClientValidationRules()
    {
        return new[] { new ModelClientValidationRequiredRule(ErrorMessage) };
    }
}

然后在Global.asax里加一句

RequiredAttributeAdapter.SelfRegister();

Technorati 标签: ASP.NET MVC 验证 国际化

完。