从C＃中的SelectList中删除项目

Question

我有一个方法，其中返回我selectList。 selectList的某些项目将基于Key以编程方式删除。

 public SelectList GetRoutingActionList()
    {
        Dictionary<string, string> routingActions = new Dictionary<string, string> { 
                                                        { "Approved", "Approve" },
                                                        { "Return To", "Return To .." }, 
                                                        { "Return To Sender", "Return To Sender" }, 
                                                        { "Disapprove", "Disapprove" },
                                                        { "Set On Hold", "Set On Hold" } 
                                                    };

        SelectList routingActionList = new SelectList(routingActions, "Key", "Value");
        return routingActionList;
    }

对于eaxmple，我必须使用Key“Disapprove”删除该项目。 任何人都可以帮助我解决这个问题。

Answer 1

你必须使用Where()来过滤它们，然后将List<SelectListItem>返回对象传递给SelectList构造函数，以获得新的SelectList，它不具有值为“Disapprove”的项目：

public class SomeController
{

   public ActionResult Index()
   {

       SelectList list = GetRoutingActionList();

       list  = new SelectList(list 
                              .Where(x => x.Value != "Disapprove")
                              .ToList(),
                              "Value",
                              "Text");

        return View();
   }

}

Answer 2

public SelectList GetRoutingActionList()
    {
        Dictionary<string, string> routingActions = new Dictionary<string, string> { 
                                                        { "Approved", "Approve" },
                                                        { "Return To", "Return To .." }, 
                                                        { "Return To Sender", "Return To Sender" }, 
                                                        { "Disapprove", "Disapprove" },
                                                        { "Set On Hold", "Set On Hold" } 
                                                    };

        SelectList routingActionList = new SelectList(routingActions, "Key", "Value");
        return routingActionList.Where(x => x.Key != "Disapprove")
                                   .ToList();
}

Answer 3

只需将其从字典中删除即可 作为参考，它将自动从SelectList中删除。

routingActions.Remove("Disapprove");