@Html.DropDownListFor 怎么在客户端验证
@Html.TextBoxFor(a => a.Title, new { style = "width:80%", maxlength = "80" })
可以实现在客户端验证

为什么 @Html.DropDownListFor( a => a.TypeId,(SelectList) ViewData["TypeId"],"—传达范围—")不行？

            <tr>

                <td width="15%">

                    标题：

                </td>

                <td colspan="3">@Html.TextBoxFor(a => a.Title, new { style = "width:80%", maxlength = "80" })

                    @Html.ValidationMessageFor(a => a.Title)

                </td>

            </tr>

            <tr>

                <td width="15%">

                    分类：

                </td>

                <td width="35%">

                    @Html.DropDownListFor( a => a.TypeId,(SelectList) ViewData["TypeId"],"—传达范围—")

                    @Html.ValidationMessageFor(a => a.TypeId)

                </td>

            </tr>

    [MetadataType(typeof(TaskMD))]

    public partial class Task

    {



 

    }

    public class TaskMD

    {

        [Required(ErrorMessage = "必须选择类型")]

        public int TypeId { get; set; }



        [Required(ErrorMessage = "必须设置【任务名称】")]

        public string Title { get; set; }

    }