function validateform(form)
{
  if (form.name.value=="")
  {
    alert("Please enter your name")
    form.name.focus()
    return (false)
  }
  if (validateemail(form.email.value)==false)
  {
    alert("Please enter a valid email address")
    form.email.focus()
    return (false)
  }
  return(true);
}

function validateemail (emailStr) {
var emailPat=/^(.+)@(.+)$/
var specialChars="\\(\\)<>@,;:\\\\\\\"\\.\\[\\]"
var validChars="\[^\\s" + specialChars + "\]"
var quotedUser="(\"[^\"]*\")"
var ipDomainPat=/^\[(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})\]$/
var atom=validChars + '+'
var word="(" + atom + "|" + quotedUser + ")"
var userPat=new RegExp("^" + word + "(\\." + word + ")*$")
var domainPat=new RegExp("^" + atom + "(\\." + atom +")*$")
var matchArray=emailStr.match(emailPat)
if (matchArray==null)
 return false
var user=matchArray[1]
var domain=matchArray[2]
if (user.match(userPat)==null)
    return false
var IPArray=domain.match(ipDomainPat)
if (IPArray!=null) {
  for (var i=1;i<=4;i++)
  {
    if (IPArray[i]>255)
      return false
  }
  return true
}
var domainArray=domain.match(domainPat)
if (domainArray==null)
    return false
var atomPat=new RegExp(atom,"g")
var domArr=domain.match(atomPat)
var len=domArr.length
if (domArr[domArr.length-1].length<2 ||
    domArr[domArr.length-1].length>4)
   return false
if (len<2)
   return false
return true;
}






<!-- bookmark this page // -->


function bookmark(url,title){
  if ((navigator.appName == "Microsoft Internet Explorer") && (parseInt(navigator.appVersion) >= 4)) {
  window.external.AddFavorite(url,title);
  } else if (navigator.appName == "Netscape") {
    window.sidebar.addPanel(title,url,"");
  } else {
    alert("Press CTRL-D (Netscape) or CTRL-T (Opera) to bookmark");
  }
}
<!--  end bookmark this page // -->
<!-- popup // -->
var vpopload;


function popload(str)
{
voppload = window.open(str,'', 'top=40, left=30, width=680,height=500, resizable, scrollbars,menubar,status');
}
<!-- end popup // -->
<!-- popup2 // -->
var vpopload2;



<!-- form submit // -->

function reg1()
{
	var ex1 = document.f1.NAME.value;
	var ex2 = document.f1.mailfrom.value;
	var ex3 = ex2.indexOf("@");
	var ex4 = ex2.indexOf(".");

	if ( ex1 == "" || ex2 == "") alert ("Please enter your name and email address");
	else

	if ( ex2.length < 7 || ex3 == -1 || ex4 == -1) alert ("Invalid email address, please re-enter");

	else
	document.f1.submit();
}
<!-- end form 1 submit with email validation // -->