JS method to control page buttons not to be submitted repeatedly during background execution_javascript skills

In ASP.NET, if you click a button and submit it to the background for execution, and then click the button again, two situations will occur. One is that the background code is executed twice, and the other is waiting for the previous one. After the submission action is executed, the submission action is executed again. No matter which one it is, the background code will be run twice, which is undesirable in many cases.
The following code has been tested in IE and Maxthon extreme speed modes.

<%@ Page Language="C# " AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %>





                                                       btn.value = "Waiting for background data update";
          btn.onclick = onDealing; Return false;
} }

div>
                                                        /form>