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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."); 

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98

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

.NET Framework

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