This is first times i met an error like this .I have also tried to find, but it is not successfully.
This is the whole my code
Here is my code
default.aspx.cs
protected void Page_Load(object sender, EventArgs e)
{
if (!base.IsPostBack)
{
switch (((base.Request.QueryString["Page"] != null) ? base.Request.QueryString["Page"].ToUpper() : "HOME"))
{
case "CONTACT":
phdDefault.Controls.Clear();
Control myUserControl = (Control)Page.LoadControl("Modules/WebUserControl.ascx");

phdDefault.Controls.Add(myUserControl);

break;
}
}
}

WebUserControl.ascx.cs


<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
<asp:Button ID="Button1" runat="server" Text="Button" onclick="Button1_Click" />
<asp:Label ID="Label1" runat="server"></asp:Label>
Code behind

protected void Button1_Click(object sender, EventArgs e)
{
// OnBubbleClick(e);
TextBox1.Text = "";
Label1.Text = "What is this an error ?";
}

Do not capture the value. on Button click

Please help me

Thanks
Phuc Hoang