TextBox1.Text = Request.QueryString in Page_Load - ASP.NET C#

[ricklafleur]

I'm using CSharp/ASP.NET 2.0 and trying to create a simple search page that records the user query in the URL (so can be bookmark) and also re-writes the query int the original TextBox. This only works once; there after the old query gets re-written to the TextBox regardless of what is entered.

I think this is because I'm using the Page_Load event which may being fired, replacing the new query with the one in the current URL, between time I enter new Text and click button ... but not sure how else to do it.

 
<!-- the search form -->
<form id="form1" runat="server">
<div>
<asp:TextBox ID="TextBox1" runat="server" OnTextChanged="TextBox1_TextChanged"></asp:TextBox>
<asp:Button ID="Button1" runat="server" Text="Button" OnClick="Button1_Click" /><br />
<asp:Label ID="Label1" runat="server" Text="Label"></asp:Label>
</div>
</form>
 

/* event to re-load the page with the query terms in the URL
 * but only works the first time when there is no value in the
 * URL
 */
protected void Button1_Click(object sender, EventArgs e)
{
Response.Redirect("Default.aspx?q=" + TextBox1.Text, true);
}
 

// write the q value from URL to search box
protected void Page_Load(object sender, EventArgs e)
{
  if (Request.QueryString["q"] != null)
  {
    TextBox1.Text = Request.QueryString["q"];
  }
}
 

Advice?

Thanks!

Rick