在視圖中傳遞MVC數據

Question

我正在製作我的MVC應用程序。我打開我的觀點與預定義的參數是這樣的：

return RedirectToAction("PickGroupForHomework", "Account", new {subject_id = id, qty=model.qty }); 

而這個工作正常，數據subject_id和qty正確傳遞。但是，我的視圖PickGroupForHomework包含一個要填充的表單，然後進行驗證。如果輸入無效，則窗口只需重新加載前面視圖中定義的數據subject_id和qty。我這樣做是這樣的：

public ActionResult PickGroupForHomework(PickGroupForHomeworkViewModel model) 
     { 
      ClassDeclarationsDBEntities2 entities = new ClassDeclarationsDBEntities2(); 
      model.groups = entities.Groups.ToList(); 
      model.users = entities.Users.ToList(); 
      int id = model.subject_id; 
      var subj = entities.Subjects 
        .Where(b => b.class_id == model.subject_id) 
        .FirstOrDefault(); 
      if (subj != null) 
      { 
       model.subject_name = subj.name; 
      } 
      if (ModelState.IsValid) 
      { 

      } 
      else 
      { 
       return View(model); 
      } 
      return View(model); 

     } 

但結果URL不包含我需要的數據，但只是一個普通的看法。我該如何做對？

Answer 1

爲了讓您的WEP應用工作，你將需要兩個動作，一個設置模型彌補了查看和另一個實際做的工作後，保存您的數據：

public ActionResult PickGroupForHomework(int subject_id, int qty) 
    { 
     //Initialize your model here. Below is just an example. 
     ClassDeclarationsDBEntities2 entities = new ClassDeclarationsDBEntities2(); 

     PickGroupForHomeworkViewModel model = new PickGroupForHomeworkViewModel(); 

     model.groups = entities.Groups.ToList(); 
     model.users = entities.Users.ToList(); 

     model.subject_id = subject_id; 
     model.qty = qty; 

     return View("PickGroupForHomework", model); 
    } 

    [HttpPost] 
    public ActionResult PickGroupForHomework(PickGroupForHomeworkViewModel model) 
    { 
     ClassDeclarationsDBEntities2 entities = new ClassDeclarationsDBEntities2(); 

     int id = model.subject_id; 

     var subj = entities.Subjects 
       .Where(b => b.class_id == model.subject_id) 
       .FirstOrDefault(); 

     if (subj != null) 
     { 
      model.subject_name = subj.name; 
     } 
     if (ModelState.IsValid) 
     { 
      //Save to database 
      [code goes here] 

      //return to a View to show your results 
      return View("[Your view to see the results]") 
     } 

     //Model Validation did not pass 
     //or exception occurred go back to View 
     return View(model); 
    }