MetadataType缺少程序集引用

Question

  using System;
  using System.Collections.Generic;
  using System.Linq;
  using System.Web;
  using System.ComponentModel.DataAnnotations;




  namespace yplaylist.Models
  {
     [MatadataType(typeof(Song_Validation))]
     public partial class Song
     {

     }

     public class Song_Validation
     {



     }
 }

MetadataType突出显示,它找不到缺少using指令或程序集引用？我错过了什么？

Answer 1

你缺少System.ComponentModel.DataAnnotations.dll参考汇编