带有.NET MVC 3 Razor Editor的HTML5占位符

带有.NET MVC 3 Razor Editor的HTML5占位符

您可以阅读以下有关编写自定义的文章

DataAnnotationsModelmetadataProvider

。

这是涉及新引入的ImetadataAware接口的另一种ASP.NET MVC 3ish更多方法。

首先创建一个实现此接口的自定义属性：

public class PlaceHolderAttribute : Attribute, ImetadataAware{    private readonly string _placeholder;    public PlaceHolderAttribute(string placeholder)    {        _placeholder = placeholder;    }    public void onmetadataCreated(Modelmetadata metadata)    {        metadata.AdditionalValues["placeholder"] = _placeholder;    }}

然后用它来装饰模型：

public class MyViewModel{    [PlaceHolder("Enter title here")]    public string Title { get; set; }}

接下来定义一个控制器：

public class HomeController : Controller{    public ActionResult Index()    {        return View(new MyViewModel());    }}

相应的视图：

@model MyViewModel@using (Html.BeginForm()){    @Html.EditorFor(x => x.Title)    <input type="submit" value="OK" />}

最后是编辑器模板（

~/Views/Shared/EditorTemplates/string.cshtml

）：

@{    var placeholder = string.Empty;    if (ViewData.Modelmetadata.AdditionalValues.ContainsKey("placeholder"))    {        placeholder = ViewData.Modelmetadata.AdditionalValues["placeholder"] as string;    }}<span>    @Html.Label(ViewData.Modelmetadata.PropertyName)    @Html.TextBox("", ViewData.TemplateInfo.FormattedModelValue, new { placeholder = placeholder })</span>