How to stop the execution of a function with JavaScript?

To stop the execution of a function in JavaScript, use the clearTimeout() method. This function call clears any timer set by the setTimeout() functions.

Example

You can try to run the following code to learn how to work with clearTimeout() method in JavaScript.

<html>
   <head>
      <title>JavaScript clearTimeout() method</title>
      <script>
         <!--
            var imgObj = null;
            var animate ;
           
            function init(){
               imgObj = document.getElementById('myImage');
               imgObj.style.position= 'relative';
               imgObj.style.left = '0px';
            }
            function moveRight(){
               imgObj.style.left = parseInt(imgObj.style.left) + 10 + 'px';
               animate = setTimeout(moveRight,20);    // call moveRight in 20msec
            }
            function stop(){
               clearTimeout(animate);
               imgObj.style.left = '0px';
            }
            window.onload = init;
         //-->
      </script>
   </head>
   <body>
      <form>
         <img id = "myImage" src = "/images/html.gif" />
         <p>Click the buttons below to handle animation</p>
         <input type = "button" value = "Start" onclick = "moveRight();" />
         <input type = "button" value = "Stop" onclick = "stop();" />
      </form>
   </body>
</html>