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UserControl.LoadViewState Method

Restores the view-state information from a previous user control request that was saved by the SaveViewState method.

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

protected override void LoadViewState(
	Object savedState
)

Parameters

savedState
Type: System.Object
An Object that represents the user control state to be restored.

This method is used primarily by the .NET Framework infrastructure and is not intended to be used directly from your code. However, control developers can override this method to specify how a custom server control restores its view state. For more information, see ASP.NET State Management Overview.

You can load a view-state value into a field so that you do not have to retrieve it from the Control.ViewState property later. You can also insert the value into the ViewState property just before calling SaveViewState , which is an effective way to make a field persist across round trips to the server.

The following example demonstrates a user control that manages its view state using the LoadViewState and SaveViewState methods.


   public string UserText
   {
	   get
	   {
		   return (string)ViewState["usertext"];
	   }
	   set
	   {
		   ViewState["usertext"] = value;
	   }
   }
   public string PasswordText
   {
	   get
	   {
		   return (string)ViewState["passwordtext"];
	   }
	   set
	   {
		   ViewState["passwordtext"] = value;
	   }
   }

   [System.Security.Permissions.PermissionSet(System.Security.Permissions.SecurityAction.Demand, Name="FullTrust")] 
   protected override void LoadViewState(object savedState) 
   {
	   object[] totalState = null;	   
	   if (savedState != null)
	   {
		   totalState = (object[])savedState;
		   if (totalState.Length != 3)
		   {
			   // Throw an appropriate exception.
		   }
		   // Load base state.
		   base.LoadViewState(totalState[0]);
		   // Load extra information specific to this control.
		   if (totalState != null && totalState[1] != null && totalState[2] != null)
		   {
			   UserText = (string)totalState[1];
			   PasswordText = (string)totalState[2];
		   }
	   }

   }

   [System.Security.Permissions.PermissionSet(System.Security.Permissions.SecurityAction.Demand, Name="FullTrust")] 
   protected override object SaveViewState()
   {
	   object baseState = base.SaveViewState();
	   object[] totalState = new object[3];
	   totalState[0] = baseState;
	   totalState[1] = user.Text;
	   totalState[2] = password.Text;
	   return totalState;
   }


.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.

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