StateBag.Add(String, Object) 方法

定義

將新 StateItem 物件加入至 StateBag 物件。Adds a new StateItem object to the StateBag object. 如果項目已經存在於 StateBag 物件中,則此方法會更新項目的值。If the item already exists in the StateBag object, this method updates the value of the item.

public:
 System::Web::UI::StateItem ^ Add(System::String ^ key, System::Object ^ value);
public System.Web.UI.StateItem Add (string key, object value);
member this.Add : string * obj -> System.Web.UI.StateItem
Public Function Add (key As String, value As Object) As StateItem

參數

key
String

StateItem 的屬性名稱。The attribute name for the StateItem.

value
Object

要加入至 StateBag 的項目值。The value of the item to add to the StateBag.

傳回

傳回 StateItem,表示加入至檢視狀態的物件。Returns a StateItem that represents the object added to view state.

例外狀況

keynullkey is null.

-或--or- key 中的字元數目為 0。The number of characters in key is 0.

範例

下列程式碼範例將示範如何使用 Add 方法。The following code example demonstrates using the Add method.

void MovePiece(string fromPosition, string toPosition) {
   StateBag bag = ViewState;
   object piece = bag[fromPosition];
   if (piece != null) {
      bag.Remove(fromPosition);
      bag.Add(toPosition, piece);
      RenderBoard();
   }
   else {
      throw new InvalidPositionException("There is no game piece at the \"from\" position."); 
   }
}
Sub MovePiece(fromPosition As String, toPosition As String)
   Dim bag As StateBag = ViewState
   Dim piece As Object = bag(fromPosition)
   If Not (piece Is Nothing) Then
      bag.Remove(fromPosition)
      bag.Add(toPosition, piece)
      RenderBoard()
   Else
      Throw New InvalidPositionException("There is no game piece at the ""from"" position.")
   End If
End Sub 'MovePiece

適用於

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