function IsEmailValid(email) {
  var Temp     = email;
  var AtSym    = Temp.indexOf('@');
  var Period   = Temp.lastIndexOf('.');
  var Space    = Temp.indexOf(' ');
  var Length   = Temp.length - 1;   // Array is from 0 to length-1
  var dom      = Temp.slice(Temp.lastIndexOf('.')+1).toLowerCase();

  if ((AtSym < 1)         ||
      (Period <= AtSym+1) ||
      (Period == Length ) ||
      (Space != -1))
  {
      /*
             ||
      (dom != 'net') &&
      (dom != 'com') &&
      (dom != 'org') &&
      (dom != 'gov') &&
      (dom != 'us')  &&
      (dom != 'mil') &&
      (dom != 'edu'))
  {  */
    return false;
  }
  return true;
}