My DropDownListFor不會從我的SelectList中選擇SelectedValue

Question

My DropDownListFor不會從我的SelectList中選擇SelectedValue，而是始終選擇第一個項目。任何解決方案

Answer 1

嗯，實際上，經過再三考慮，仔細檢查sublegerType_Id？我不確定它應該是Id。我認爲它需要成爲實際的對象。

例如，這不工作（默認爲第一項）

 List<Tuple<string, string>> NumberList = new List<Tuple<string, string>>(); 
     for (int i = 0; i < 5; i++) 
     { 
      NumberList.Add(new Tuple<string, string>(i.ToString(),i.ToString())); 
     } 
     NumberSelectList = new SelectList(NumberList,"2"); 

但這工作好（默認爲的（4,4）所選擇的項目）

 List<Tuple<string, string>> NumberList = new List<Tuple<string, string>>(); 
     Tuple<string, string> selectedObject = new Tuple<string, string>("-1","-1"); 
     for (int i = 0; i < 5; i++) 
     { 
      if (i == 4) 
      { 
       selectedObject = new Tuple<string, string>(i.ToString(), i.ToString()); 
       NumberList.Add(selectedObject); 
      } 
      else 
       NumberList.Add(new Tuple<string, string>(i.ToString(), i.ToString())); 


     } 
     NumberSelectList = new SelectList(NumberList, selectedObject);