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The following is a "Hello World" kind of code for ViewState. I just want to know how to retain the ViewState 1) while Page Refresh when using UpdatePanel and also 2) While I reverting back to the page after round trip when using UpdatePanel?
In the following code snippet the ViewState is killed when I click page refresh or when I go some page and revert back
Code Snippet:
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- // Default.aspx:
- <%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Default.aspx.cs" Inherits="ASPCS2008ViewState._Default"
- EnableViewState="true" ViewStateEncryptionMode="Always" %>
- <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
- <script runat="server">
- private int Counter
- {
- get
- {
- object Instance = ViewState["Counter"];
- return (Instance == null) ? 0 : (int)Instance;
- }
- set
- {
- ViewState["Counter"] = value;
- }
- }
- protected void Button1_Click(object sender, EventArgs e)
- {
- Counter++;
- TextBox1.Text = Counter.ToString();
- }
- protected void Button2_Click(object sender, EventArgs e)
- {
- Response.Redirect("SomePage.aspx");
- }
- </script>
- <html xmlns="http://www.w3.org/1999/xhtml" >
- <head runat="server">
- <title></title>
- </head>
- <body>
- <form id="form1" runat="server" >
- <asp:ScriptManager ID="ScriptManager1" runat="server" />
- <asp:UpdatePanel ID="UpdatePanel1" runat="server" >
- <ContentTemplate>
- <div>
- <asp:Button ID="Button1" runat="server" Text="Click" onclick="Button1_Click" />
- <br />
- <br />
- <span lang="en-us">
- <asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
- <br />
- </span>
- <br />
- <asp:Button ID="Button2" runat="server" Text="Go Some Page"
- onclick="Button2_Click" />
- <br />
- <br />
- </div>
- </ContentTemplate>
- </asp:UpdatePanel>
- </form>
- </body>
- </html>
- // SomePage.aspx
- <%@ Page Language="C#" AutoEventWireup="true" CodeBehind="SomePage.aspx.cs" Inherits="ASPCS2008ViewState.SomePage"
- EnableViewState="true" ViewStateEncryptionMode="Always" %>
- <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
- <script runat="server">
- protected void Button2_Click(object sender, EventArgs e)
- {
- Response.Redirect("Default.aspx");
- }
- </script>
- <html xmlns="http://www.w3.org/1999/xhtml" >
- <head runat="server">
- <title></title>
- </head>
- <body>
- <form id="form1" runat="server">
- <asp:ScriptManager ID="ScriptManager1" runat="server"></asp:ScriptManager>
- <asp:UpdatePanel ID="UpdatePanel1" runat="server" >
- <ContentTemplate>
- <p>
- <span lang="en-us">Wellcome to Some Page! </span>
- </p>
- <p>
- <asp:Button ID="Button2" runat="server" Text="Go back" onclick="Button2_Click" />
- </p>
- <div>
- </div>
- </ContentTemplate>
- </asp:UpdatePanel>
- </form>
- </body>
- </html>
Thanks
