Question

我有一个简单方法的测试控制器：

private ApplicationEntities _db = new ApplicationEntities();

public String GetSomeString()
{
    return _db.someStoredProcedure(8).SingleOrDefault();
}

这在控制器中工作正常，并说该方法返回＆＃34; Hello＆＃34; 它出现在ViewModel中时会出现问题。我把它简化为：

public class TestView
{
   private ApplicationEntities _db = new ApplicationEntities();

   private string smth;

   public String Something
   {
     get {
        //This line does not work here. 
       Error    5   'System.Data.Entity.Core.Objects.ObjectResult<string>' does not contain a definition for 'SingleOrDefault' and no extension method 'SingleOrDefault' accepting a first argument of type 'System.Data.Entity.Core.Objects.ObjectResult<string>' could be found (are you missing a using directive or an assembly reference?)

        var d = _db.someStoredProcedure(8).SingleOrDefault();

         //This works, since the result is always only 1 row
        var a = _db.someStoredProcedure(8).GetEnumerator();
        var b = a.MoveNext();
        var c = a.Current;
           return a.Current;
        }
        set { smth= value; }
     }

    public async static void getString()
    {
       var a = new TestView().Something;
    }


}

问题是为什么SingleOrDefault（）不能在这里工作？（没有可以轻松添加的程序集引用）以及如何更好地解决此ViewModel和getString方法？

MVC 5 - SingleOrDefault方法无法在ViewModel

0 个答案: