当我在add函数中添加Submit函数时，为什么该程序无法工作？

Question

It works until I add the click function inside the add function.

How to make it work such that when add function is called from within the check function the flag is incremented only when the user clicks the submit button and then the control is passed back to check function so the correct final value should be 3.

 var flag = 1; if(flag == 1) { $('p').html("xxx"); check(); } function check() { $('#submit').click(function() { if($("#text").val()=="") { alert("Enter some text"); } else { add(); flag++; alert(flag); } }); } function add() { $('#submit').click(function() { flag++; alert("inside add " + flag); }); } 

 <script src="https://code.jquery.com/jquery-3.3.1.min.js" integrity="sha256-FgpCb/KJQlLNfOu91ta32o/NMZxltwRo8QtmkMRdAu8=" crossorigin="anonymous"></script> <div id="myform"> <p id="title"></p> <input type="text" id="text"> <input type="submit" id="submit"> </div> 

Answer 1

You need to add $( document ).ready(function() { ... });

this seems to work as you aspected:

  $( document ).ready(function() { var flag = 1; if(flag == 1) { $('p').text("xxx"); check(); } function check() { $('#submit').click(function() { if($("#text").val()=="") { alert("Enter some text"); } else { add(); flag++; alert(flag); } }); } function add() { $('#submit').click(function() { flag++; alert("inside add " + flag); } )}; }); 

 <script src="https://code.jquery.com/jquery-3.3.1.min.js" integrity="sha256-FgpCb/KJQlLNfOu91ta32o/NMZxltwRo8QtmkMRdAu8=" crossorigin="anonymous"></script> <div id="myform"> <p id="title"></p> <input type="text" id="text"> <input type="submit" id="submit"> </div>