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Page.EnableViewState Property

Gets or sets a value indicating whether the page maintains its view state, and the view state of any server controls it contains, when the current page request ends.

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

'Declaration
<BrowsableAttribute(False)> _
Public Overrides Property EnableViewState As Boolean
<asp:Page EnableViewState="True|False" />

Property Value

Type: System.Boolean
true if the page maintains its view state; otherwise, false. The default is true.

For information about why you might want to disable view state, see Control.EnableViewState.

Even if EnableViewState is false, the page might contain a hidden view state field that is used by ASP.NET to detect a postback.

The following code example sets the EnableViewState property to false when the page is loaded. This disables view state for the Page object, meaning that neither view-state information for the page nor any controls contained by the page are saved.

Security noteSecurity Note

This example has a text box that accepts user input, which is a potential security threat. By default, ASP.NET Web pages validate that user input does not include script or HTML elements. For more information, see Script Exploits Overview.

Public Class WebPage
   Inherits System.Web.UI.Page
   Private myFormObj As MyForm
   Private label1 As Label
   Private label2 As Label
   Private textBoxObj As TextBox
   Private buttonObj As Button

   Public Sub New()
      AddHandler Page.Init, AddressOf Page_Init
   End Sub 'New 


   Private Sub Page_Load(sender As Object, e As System.EventArgs)
      ' Comment the following line to maintain page view state.
      Page.EnableViewState = false
      myFormObj.Method = "post"
      Controls.Add(myFormObj)
      textBoxObj.Text = "Welcome to .NET"

      label1.Text = "Enter a name"
      buttonObj.Text = "ClickMe" 
      AddHandler buttonObj.Click, AddressOf Button_Click
      myFormObj.Controls.Add(label1)
      myFormObj.Controls.Add(textBoxObj)
      myFormObj.Controls.Add(buttonObj)
      myFormObj.Controls.Add(label2)
   End Sub 'Page_Load

   Private Sub Button_Click(sender As Object, e As EventArgs)
      Dim temp As [String] = "<br>Name is " + textBoxObj.Text + "<br>"
      temp += "Saved content of previous page is " + CType(ViewState("name"), String)
      label2.Text = temp
   End Sub 'Button_Click

   Protected Overrides Sub LoadViewState(viewState As Object)
      If Not (viewState Is Nothing) Then 
         MyBase.LoadViewState(viewState)
      End If 
   End Sub 'LoadViewState

   Protected Overrides Function SaveViewState() As Object
      ViewState("name") = textBoxObj.Text
      Return MyBase.SaveViewState()
   End Function 'SaveViewState

   Private Sub Page_Init(sender As Object, e As EventArgs)
      AddHandler Me.Load, AddressOf Me.Page_Load
      myFormObj = New MyForm()
      label1 = New Label()
      label2 = New Label()
      textBoxObj = New TextBox()
      buttonObj = New Button()
   End Sub 'Page_Init
End Class 'WebPage

.NET Framework

Supported in: 4.5.2, 4.5.1, 4.5, 4, 3.5, 3.0, 2.0, 1.1, 1.0

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

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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