Javascript return false not working -

guys code returning false in blank page after submit.what error of code.

function send_serial(){     //check date     var date=document.getelementbyid('date_field').value;     if(date==''||date==null){     alert('please select date.');         return false;   }    } 

your form tag should be

<form onsubmit="return send_serial();">  

not

<form action="javascript:send_serial();">  

when use javascript:send_serial action, you're asking form resubmit page content supplied result of send_serial function.

the onsubmit event handler javascript, not url, doesn't need javascript: in front. if result of event handler false, cancel form submission. can't onsubmit="send_serial()" because result of action handler nothing. action handler function body plugged function (event) { ... } need have return in onsubmit attribute.