Question

I have a problem with Request.QueryString that returns a null value. I think that is from OutputCache

I have in Default.aspx (with master file)

<%@ OutputCache Duration="60" VaryByParam="button" %>

<script runat="server">
   protected void Page_Load( object sender, EventArgs e ) {
      TimeMsg.Text = DateTime.Now.ToString( "G" );
      string v = Request.QueryString["button"];
      PageName.Text = v;
   }
</script>

<form method="get" action="Default.aspx">
   <h5>Click a button</h5>
   <input type="submit" name="button" value="One" />
   <input type="submit" name="button" value="Two" />
   <input type="submit" name="button" value="Three" />
   </form>



   <p>Page generated at : <asp:Label ID="TimeMsg" runat="server"></asp:Label></p>
   <p>Page name : <asp:Label ID="PageName" runat="server"></asp:Label></p>

I don’t write anymore the <asp:Content ID='' ...></asp> tag.

When I press one of button, the PageName returns empty that I checked the v variable with Debugger and I see that it returns null.

Why ?

Answer 1

If you change Request.QueryString["button"]; to Request.Form["button"]; you will get the expected output. This is probably because of Form in your master page.