Disable button and show loading message while user clicked in asp.net c# NOT USING UpdatePanel

 HTML
<form id="form1" runat="server"> 
        <asp:Button ID="Button1" runat="server" Text="Button" />
</form>

Codebehind
protected void Page_Load(object sender, System.EventArgs e) 
{
        Button1.Attributes.Add("onclick", (ClientScript.GetPostBackEventReference(Button1, "") + ";this.value=\'Loading...\';this.disabled = true;"));
}

class Default_ : System.Web.UI.Page 
{

protected void Button1_Click(object sender, System.EventArgs e) 
{
        System.Threading.Thread.Sleep(555);
          //Some additional logic here
          ** Without Masterpage **
        ClientScript.RegisterClientScriptBlock( this.GetType(), "reset", 
          ("document.getElementById(\'" + (Button1.ClientID + "\').disabled=false;")), true);

          ** With Masterpage **
        ScriptManager.RegisterClientScriptBlock(this,true.GetType(), "reset", 
         ("document.getElementById(\'" + (Button1.ClientID + "\').disabled=false;")), true);
}


}
NOTE : This will not work if you are using UpdatePanel. If you are using UpdatePanel, see here.
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