Pass parameters to the function:
Click the Start button to output "Hello" once every 2 seconds.
<!DOCTYPE html> <html> <body> <button onclick="myStartFunction()">Start</button> <button onclick="myStopFunction()">Stop</button> <p id="demo"></p> <p id="demo2" style="color:red;"></p> <script> var myVar;//from www. ja va 2 s. c o m function myStartFunction() { myVar = setInterval(alertFunc, 2000, "First parameter", "Second parameter"); } function alertFunc(param1, param2) { document.getElementById("demo").innerHTML += "Hello "; document.getElementById("demo2").innerHTML = "Parameters passed to alertFunc(): <br>" + param1 + "<br>" + param2 + "<br>"; } function myStopFunction() { clearInterval(myVar); } </script> </body> </html>