signup.php

<?php

require_once 'header.php';

echo <<<_END
<script>
function checkUser(user)
{
  if(user.value=='')
  {
    O('info').innerHTML=''
    return
  }

params = "user="+user.value
request =new ajaxRequest()
request.open("POST","checkuser.php",true)

request.setRequsetHeader("Content-type","application/x-www-form-urlencoded")
request.setRequsetHeader("Content-length",params.length)
request.setRequsetHeader("Connection","close")

request.onreadystatechange=function(){
  if(this.readyState==4 && this.status=200 && this.responseText!=null)
    O('info').innerHTML = this.responseText

}
request.send(params)

}



function ajaxRequest()
{
  try{var request = new XMLHttpRequest()}
  catch(e1){
    try {request=new ActiveXObject("Msxm12.XMLHTTP")}
    catch(e2)
    {
      try {request = new ActiveXObject("Microsoft.XMLHTTP")}
      catch(e3){request=false}
    }
  }
  return request
}

</script>
<div class='main'><h3>Please enter your details to sign up</h3>
_END;

$error= $user =$pass="";
if(isset($_SESSION['user'])) destorySession();
if(isset($_POST['user']))
{
  $user = sanitizeString($_POST['user']);
  $pass = sanitizeString($_POST['pass']);
  if($user==""||$pass=="")
  {
    $error= "Not all fields were entered<br><br>";
  }
  else
  {
    $result = queryMysql("SELECT * FROM members WHERE user='$user'");
    if($result->num_rows)
    $error="That username already exists<br><br>";
    else
    {
      queryMysql("INSERT INTO members VALUES('$user','$pass')");
      die("<h4>Acconunt created </h4> Please log in.<br><br>");
    }
  }
}

echo <<<_END
<form method ='post' action='signup.php'>$error
<span class ='fieldname'>Username</span>
<input type ='text' maxlength='16' name ='user' value='$user'
onBlur ='checkUser(this)'><span id='info'></span><br>
<span class ='fieldname'>Password</span>
<input type='text' maxlength ='16' name='pass' value='$pass'><br>

_END;
 ?>


<span class='fieldname'>&nbsp;</span>
<input type ='submit' value='Sign up'>
</form></div><br>
</body>
</html>