function echeck(str) {
   var at = "@"
   var dot = "."
   var lat = str.indexOf(at)
   var lstr = str.length
   var ldot = str.indexOf(dot)
   if (str.indexOf(at) ==- 1) {
      alert("Invalid E-mail address"); return false}
   if (str.indexOf(at) ==- 1 || str.indexOf(at) == 0 || str.indexOf(at) == lstr) {
      alert("Invalid E-mail address"); return false}
   if (str.indexOf(dot) ==- 1 || str.indexOf(dot) == 0 || str.indexOf(dot) == lstr) {
      alert("Invalid E-mail address"); return false}
   if (str.indexOf(at, (lat + 1)) !=- 1) {
      alert("Invalid E-mail address"); return false}
   if (str.substring(lat - 1, lat) == dot || str.substring(lat + 1, lat + 2) == dot) {
      alert("Invalid E-mail address"); return false}
   if (str.indexOf(dot, (lat + 2)) ==- 1) {
      alert("Invalid E-mail address"); return false}
   if (str.indexOf(" ") !=- 1) {
      alert("Invalid E-mail address"); return false}
   return true }
   
function ValidateForm() {
   var emailID = document.getElementById("email");
   var name = document.getElementById("fullname");
   if ((name.value == null) || (name.value == "")) {
      alert("Please enter your name"); name.focus(); return false}
   if ((emailID.value == null) || (emailID.value == "")) {
      alert("Please enter your Email address"); emailID.focus(); return false}
   if (echeck(emailID.value) == false) {
      emailID.value = ""; emailID.focus(); return false}
   return true}