Registers a control with the page as one requiring view-state encryption.
(in System.Web.dll)
Visual Basic (Declaration)
Public Sub RegisterRequiresViewStateEncryption
Dim instance As Page
instance.RegisterRequiresViewStateEncryption()
public void RegisterRequiresViewStateEncryption()
public:
void RegisterRequiresViewStateEncryption()
public function RegisterRequiresViewStateEncryption()
| Exception | Condition |
|---|
| InvalidOperationException | The RegisterRequiresViewStateEncryption method must be called before or during the page PreRenderphase in the page life cycle. |
If you are developing a custom control that deals with potentially sensitive information, call the RegisterRequiresViewStateEncryption method to register the control with the page and ensure view state for the control is encrypted.
The entire page state will be encrypted if the ViewStateEncryptionMode is set to Auto or Always.
The following code example demonstrates setting the view-state encryption mode for a Page object and requesting encryption of the view state through RegisterRequiresViewStateEncryption. In this example, view state will be encrypted when customer information is retrieved from a database.
<%@ Page Language="VB" AutoEventWireup="true" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)
If IsPostBack Then
If (yesRetrieve.Checked) Then
Page.RegisterRequiresViewStateEncryption()
Dim conn As System.Data.SqlClient.SqlConnection = _
New System.Data.SqlClient.SqlConnection _
("server=localhost;database=Northwind;Integrated Security=SSPI")
Dim command As System.Data.SqlClient.SqlCommand = _
conn.CreateCommand()
command.CommandText = "Select [CustomerID] From [Customers]"
conn.Open()
Dim reader As System.Data.SqlClient.SqlDataReader = _
command.ExecuteReader()
customerid.Text = reader("CustomerID").ToString()
reader.Close()
conn.Close()
End If
End If
End Sub
</script>
<html >
<head id="Head1" runat="server">
<title>Customer Information</title>
</head>
<body>
<form id="form1" runat="server">
<div>
Customer identifier:
<asp:Label ID="customerid" runat="server" Text="Not available" />
<br />
Retrieve customer info:
<asp:RadioButton ID="yesRetrieve" Text="yes" runat="server" GroupName="group1" />
<asp:RadioButton ID="noRetrieve" Text="no" runat="server" GroupName="group1" />
<br />
<asp:Button ID="Button1" runat="server" Text="Submit" />
</div>
</form>
</body>
</html>
<%@ Page Language="C#" AutoEventWireup="true" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
void Page_Load(Object sender, EventArgs e)
{
if (IsPostBack)
{
if (yesRetrieve.Checked)
{
Page.RegisterRequiresViewStateEncryption();
System.Data.SqlClient.SqlConnection conn =
new System.Data.SqlClient.SqlConnection
("server=localhost;database=Northwind;Integrated Security=SSPI");
System.Data.SqlClient.SqlCommand command =
conn.CreateCommand();
command.CommandText = "Select [CustomerID] From [Customers]";
conn.Open();
System.Data.SqlClient.SqlDataReader reader =
command.ExecuteReader();
customerid.Text = reader["CustomerID"].ToString();
reader.Close();
conn.Close();
}
else
{
customerid.Text = "Not retrieved";
}
}
}
</script>
<html >
<head id="Head1" runat="server">
<title>Customer Information</title>
</head>
<body>
<form id="form1" runat="server">
<div>
Customer identifier:
<asp:Label ID="customerid" runat="server" Text="Not available" />
<br />
Retrieve customer info:
<asp:RadioButton ID="yesRetrieve" Text="yes" runat="server" GroupName="group1" />
<asp:RadioButton ID="noRetrieve" Text="no" runat="server" GroupName="group1" />
<br />
<asp:Button ID="Button1" runat="server" Text="Submit" />
</div>
</form>
</body>
</html>
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
Reference