function isValidEmail(str) {   return (str.indexOf(".") > 2) && (str.indexOf("@") > 0);}

function Validatelogin() {
emailtest = Userinfo.email.value;
emailresult = isValidEmail(emailtest);

 if (Userinfo.username.value == ""){
  alert("Please fill in your username");
  Userinfo.username.focus();
 }else if (Userinfo.email.value == ""){
  alert("Please fill in your email address");
  Userinfo.email.focus();
 }else if (emailresult == false && Userinfo.email.value != "") {
 alert("Please fill in a valid email address");
 Userinfo.email.focus();
 }else if (Userinfo.password.value == ""){
  alert("Please fill in your password");
  Userinfo.password.focus();
 }else if (Userinfo.password_confirm.value == ""){
    alert("Please fill in your confirm password");
  Userinfo.password_confirm.focus();
 }else if (Userinfo.password.value != Userinfo.password_confirm.value ){
   alert("Your password does not match your confirm password");
 }else if (Userinfo.realname.value == ""){
    alert("Please fill in your name");
  Userinfo.realname.focus();
 }else if (Userinfo.ICno.value == ""){
    alert("Please fill in your real IC number");
  Userinfo.ICno.focus();
 } else if (Userinfo.contactno.value == ""){
    alert("Please fill in your contact number");
  Userinfo.contactno.focus();
 }else if (Userinfo.address1.value == ""){
    alert("Please fill in your address");
  Userinfo.address1.focus();
 }else if (Userinfo.postcode.value == ""){
 alert("Please fill in the postcode");
   Userinfo.postcode.focus();
 }else {
   Userinfo.submit();
 };
}