Error with form validation (javascript) -

i have following html code:

<form name="register" action="register.aspx" method="post" runat="server" style="margin-top: 15px;" onsubmit="return validateprofile(formname='register');" >   <p> name* : <input id="firstname" type="text" name="firstname"/> </p> <form> 

and javascript code:

function isempty(field) {          if (field == "" || field == null)     return false; }  function validateprofile(formname) {     var errfname = "";     var fname = document.forms[formname]["firstname"].value;     alert(isempty(field=fname));     return false; } 

the problem here validation doesn't work...

i want if field empty there alert message. solution might simple, start leran validtion javascript.

i have used isempty function in code.

change

validateprofile(formname='register'); 

to

validateprofile('register'); 

and

alert(isempty(field=fname)); 

to

   alert(isempty(fname));   function validateprofile(formname) {     var errfname = "";     var fname = document.forms[formname]["firstname"].value;     return isempty(fname); }