How to open print dialog box in JavaScript

How to pop-up print dialog box from html page or link or button using JavaScript.

Here is the example to print open a content of a page in another window and print them.

function CallPrint(strid)

 {

           var prtContent = document.getElementById(strid);

         var WinPrint = window.open('', '', 'letf=100,top=100,width=600,height=600,toolbar=0,scrollbars=1,status=0');

            WinPrint.document.write(prtContent.innerHTML);

            WinPrint.document.close();

            WinPrint.focus();

            WinPrint.print();

            //WinPrint.close()   

 }