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StateBag.Add Method

Adds a new StateItem object to the StateBag object. If the item already exists in the StateBag object, this method updates the value of the item.

Namespace:  System.Web.UI
Assembly:  System.Web (in System.Web.dll)

public StateItem Add(
	string key,
	Object value


Type: System.String
The attribute name for the StateItem.
Type: System.Object
The value of the item to add to the StateBag.

Return Value

Type: System.Web.UI.StateItem
Returns a StateItem that represents the object added to view state.


key is null.

- or -

The number of characters in key is 0.

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.Add(toPosition, piece);
   else {
      throw new InvalidPositionException("There is no game piece at the \"from\" position."); 

.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.