PHP - Input Validation In Jquery/js

This topic has been moved to JavaScript Help.

http://www.phpfreaks.com/forums/index.php?topic=359169.0

Hi there, I am using the jQuery, Ajax PHP code which is given at http://roshanbh.com.np/2008/04/ajax-login-validation-php-jquery.html

The form I am using, which is in index.html, is:
Code: [Select]
<form method="post" action="" name="login" id="login_form">
                    <div class="field_row">
                        <div class="label_container">
            <label>Email</label>                       
                        </div>
                        <div class="field_container">
            <input type="text" placeholder="login with your email address..." name="email_address" id="email_address" value="" class="large" />                       
                        </div>
        <div class="clear"><span class="nodisp">&nbsp;</span></div>
        </div>

        <div class="field_row">
            <div class="label_container">
            <label>Password</label>         
            </div>
            <div class="field_container">
            <input type="password" placeholder="...and password" name="password" id="password" value="" class="large" />         
            </div>
        <div class="clear"><span class="nodisp">&nbsp;</span></div>
        </div>
               
                    <div class="final_row">
                        <input type="image" src="images/login_blue.gif" id="user_login_button" name="user_login_button" value="login" id="submit" class="submit_button" />
                        <div class="final_row_text_container" >
<a href="/login/forgot_password" style="color: #008ee8;" class="small_text">Forgot your Password?</a>
                        <br />
<span id="msgbox" style="display:none"></span>
</div>
                    </div>
<div class="clear"><span class="nodisp">&nbsp;</span></div>

                </form>

The Javascript, which is situated in the head of index.html. is:
Code: [Select]
<script language="javascript">
$(document).ready(function()
{
$("#login_form").submit(function()
{
//remove all the class add the messagebox classes and start fading
$("#msgbox").removeClass().addClass('messagebox').text('Validating....').fadeIn(1000);
//check the email address exists or not from ajax
$.post("login_ajax.php",{ email_address:$('#email_address').val(),password:$('#password').val(),rand:Math.random() } ,function(data)
        {
  if(data=='yes') //if correct login detail
  {
  $("#msgbox").fadeTo(200,0.1,function()  //start fading the messagebox
{
  //add message and change the class of the box and start fading
  $(this).html('Logging in.....').addClass('messageboxok').fadeTo(900,1,
              function()
  {
  //redirect to secure page
document.location='secure.php';
  });
 
});
  }
  else
  {
  $("#msgbox").fadeTo(200,0.1,function() //start fading the messagebox
{
  //add message and change the class of the box and start fading
  $(this).html('Your login details are incorrect.').addClass('messageboxerror').fadeTo(900,1);
});
          }

        });
  return false; //not to post the  form physically
});
//now call the ajax also focus move from
$("#password").blur(function()
{
$("#login_form").trigger('submit');
});
});
</script>

And the PHP, in login_ajax.php, is:

<?php session_start();

$host =  "localhost";
$user = "bford";
$pass = "bford";
$db = "bford";

$link = mysql_connect($host, $user, $pass);
if (!link) 
{
die('<strong>Error(s) occured:</strong> Could not connect: ' . mysql_error());
}

$db_selected = mysql_select_db($db, $link);
if (!db_selected) 
{
die ('<strong>Error(s) occured:</strong> Cant use bford: ' . mysql_error());
}

//get the posted values
$email_address=$_GET['emailaddress'];
$pass=$_GET['password'];

//now validating the username and password
$sql="SELECT * FROM users WHERE email_address='".$email_address."'";
$result=mysql_query($sql);
$row=mysql_fetch_array($result);

//if username exists
if(mysql_num_rows($result)>0)
{
//compare the password
if($row["password"],$pass)==1
{
echo "yes";
//now set the session from here if needed
$_SESSION["user_name"]=$userID; 
}
else
echo "no"; 
}
else
echo "no"; //Invalid Login


?>


I have been working on this for days now, changing around the form names, database table names, php variables, allsorts! I still cannot get it functioning properly. When I input a correct email_address and password combination, the 'Your login details are incorrect.' message still appears.

Help would be much appreciated.

Ben.

Where in the PHP manual can I find information about input validation? I looked and I seem to not find it.

I am intending to create my own email input validation.

i'm really sorry, if there is a word that makes you confused.

 

Code: [Select]
<?php
$ip = $_SERVER['REMOTE_ADDR'];

if($_POST['hapus']=='Hapus')
{
$qDelDetail = mysql_query("DELETE FROM tbl_u_pekerjaan WHERE id_u_pekerjaan = '".$_POST['id_u_pekerjaan']."'");
}
?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
<title>Untitled Document</title>
<style>
.suggestion {
position:absolute;
background-color:#eee;
    border:1px solid #CCC;
    display: none;
    width:400px;
}

.suggestion ul{
    margin : 0 ;
    padding : 5px 5px ;
}

.suggestion ul li{
    padding-top : 2px ;
    cursor : pointer ;
    list-style : none ;
}

.suggestion ul li:hover{
    cursor : pointer ;
    list-style : none ;
    color : red ;
    /*font-weight : bold ;*/
}
#form1 #pagu1 {
border: 1px solid #999999;
height: 21px;
width: 355px;
}
</style>
</head>

<body>
<table width="100%" border="0" cellspacing="0" cellpadding="0">
  <tr>
    <td class="border_all" height="34" bgcolor="#CCCCCC"><strong><img src="image/icon_1.png" align="absmiddle" width="22" height="22" /> Pemeliharaan Komputer </strong></td>
  </tr>
  <tr>
    <td><hr size="1" color="#999999" /></td>
  </tr>
  <tr>
    <td>
      <table width="100%" border="0" cellspacing="2" cellpadding="3">
<form id="form1" name="form1" method="post" action="">
        <tr>
      <td width="30%">Tahun Anggaran</td>
      <td width="2%">:</td>
      <td width="68%"><select name="thn_anggaran" id="thn_anggaran">
            <?php
  $thn_on = date("Y");
?>
            <option value="<?=$thn_on;?>"><?=$thn_on;?></option>
<?php
  for($i = 2000; $i <= $thn_on; $i++)
  {
  ?>
            <option value="<?=$i;?>"><?=$i;?></option>
            <?php
  }
  ?>
          </select></td>
    </tr>   
        <tr>
      <td width="30%">Jenis Anggaran</td>
      <td width="2%">:</td>
      <td width="68%"><select name="id_jns_anggaran">
  <?php
  include "conn_ra.php";
  ?>
              <?php
  $qRea = mysql_query("SELECT * FROM tbl_jns_anggaran ORDER BY id_jns_anggaran ASC");
  while($dtRea = mysql_fetch_array($qRea))
  {
  ?>
              <option value="<?=$dtRea['id_jns_anggaran'];?>"><?=$dtRea['nm_jns_anggaran'];?></option>
              <?php 
  }
  ?>
          </select></td>
    </tr>
        <tr>
          <td align="left" valign="top">Nama Program</td>
          <td align="left" valign="top">:</td>
          <td align="left" valign="top"><input type="text" id="kd_program" name="kd_program" size="8" onkeyup="javascript:suggestme('program');" autocomplete="off" />
              <input type="text" id="nm_program" name="nm_program" size="50" onkeyup="javascript:suggestme('program');" autocomplete="off" />
              <div id="suggestion_program" class="suggestion"></div></td>
        </tr>
        <tr>
          <td align="left" valign="top">Nama Kegiatan</td>
          <td align="left" valign="top">:</td>
          <td align="left" valign="top"><input type="text" id="kd_kegiatan" name="kd_kegiatan" size="8" onkeyup="javascript:suggestme('kegiatan');" autocomplete="off" />
              <input type="text" id="nm_kegiatan" name="nm_kegiatan" size="50" onkeyup="javascript:suggestme('kegiatan');" autocomplete="off" />
              <div id="suggestion_kegiatan" class="suggestion"></div></td>
        </tr>
        <tr>
          <td align="left" valign="top">Nama Sub Kegiatan</td>
          <td align="left" valign="top">:</td>
          <td align="left" valign="top"><input type="text" id="kd_sub_kegiatan" name="kd_sub_kegiatan" size="8" onkeyup="javascript:suggestme('sub_kegiatan');" autocomplete="off" />
              <input type="text" id="nm_sub_kegiatan" name="nm_sub_kegiatan" size="50" onkeyup="javascript:suggestme('sub_kegiatan');" autocomplete="off" />
              <div id="suggestion_sub_kegiatan" class="suggestion"></div></td>
        </tr>
        <tr>
          <td align="left" valign="top">MAK</td>
          <td align="left" valign="top">:</td>
          <td align="left" valign="top"><input type="text" id="kd_mak" name="kd_mak" size="8" onkeyup="javascript:suggestme('mak');" autocomplete="off" />
              <input type="text" id="nm_mak" name="nm_mak" size="50" onkeyup="javascript:suggestme('mak');" autocomplete="off" />
              <div id="suggestion_mak" class="suggestion"></div></td>
        </tr>
        <!--
<tr>
          <td align="left" valign="top"><strong>Pagu</strong></td>
          <td align="left" valign="top"><strong>:</strong></td>
          <td align="left" valign="top"><div id="pagu1"></div>
              <input name="pagu" type="text" id="pagu" size="60"  maxlength="250" /></td>
        </tr>
-->
        <tr>
          <td width="30%"> Komputer </td>
          <td width="2%">:</td>
          <td width="68%"><select name="id_inventaris" id="id_inventaris">
          <?php
  include "conn.php";
  if(isset($_POST['id_inventaris']))
  {
  $qKomputer = mysql_query("SELECT a.id_inventaris, a.nmr_inventaris, a.merk, a.type, a.processor_type FROM v_inventaris a WHERE id_inventaris = '".$_POST['id_inventaris']."'");
  $dtKomputer = mysql_fetch_array($qKomputer);
  ?>
          <option value="<?=$dtKomputer['id_inventaris']?>"><?=$dtKomputer['nmr_inventaris'];?> | <?=$dtKomputer['merk'];?> <?=$dtKomputer['type'];?> <?=$dtKomputer['processor_type'];?></option>
           <?php
   }else
   {
   ?>
<option>-Pilih Komputer-</option>
<?php
}
?>
          <?php
  $qKomputer = mysql_query("SELECT a.id_inventaris, a.nmr_inventaris, a.merk, a.type, a.processor_type FROM v_inventaris a WHERE EXISTS ( SELECT b.id_inventaris FROM tbl_memiliki b WHERE a.id_inventaris = b.id_inventaris ) ORDER BY id_inventaris ASC");
  while($dtKomputer = mysql_fetch_array($qKomputer))
  {
  ?>
          <option value="<?=$dtKomputer['id_inventaris']?>"><?=$dtKomputer['nmr_inventaris'];?> | <?=$dtKomputer['merk'];?> <?=$dtKomputer['type'];?> <?=$dtKomputer['processor_type'];?></option>
          <?
  }
  ?>
          </select>          </td>
        </tr>
        <tr>
          <td>Jenis Pemeliharaan </td>
          <td>:</td>
          <td><select name="id_jenis" id="id_jenis">
          <?php
  include "conn.php";
  if(isset($_POST['id_jenis']))
  {
  $qJenis = mysql_query("SELECT * FROM tbl_jenis WHERE id_jenis = '".$_POST['id_jenis']."'");
  $dtJenis = mysql_fetch_array($qJenis);
  ?>
    <option value="<?=$dtJenis['id_jenis'];?>"><?=$dtJenis['nm_jenis'];?></option>
          <?php
  }else
  {
  ?>
    <option>-Pilih Jenis Pemeliharaan-</option>
          <?php
  }
  ?>
  <?php
  $qJenis = mysql_query("SELECT * FROM tbl_jenis ORDER BY id_jenis ASC");
  while($dtJenis = mysql_fetch_array($qJenis))
  {
  ?>
    <option value="<?=$dtJenis['id_jenis'];?>"><?=$dtJenis['nm_jenis'];?></option>
  <?
  }
  ?>
          </select>          </td>
        </tr>
        <tr>
          <td>No. Surat/Memo</td>
          <td>:</td>
          <td><input name="no_surat" type="text" id="no_surat" size="50" /></td>
        </tr>
        <tr>
          <td>Tanggal Surat/Memo </td>
          <td>:</td>
          <td><input name="tgl_surat" type="text" id="tgl_surat" size="10" value="<?=$_POST['tgl_surat'];?>" />
            <script language="JavaScript" type="text/javascript">
new tcal ({
// form name
'formname': 'form1',
// input name
'controlname': 'tgl_surat'
});
</script></td>
        </tr>
        <tr>
          <td>Asal Surat </td>
          <td>:</td>
          <td><input name="asal_surat" type="text" id="asal_surat" size="50" /></td>
        </tr>
        <tr>
          <td>Penanggung Jawab Pemeliharaan </td>
          <td>:</td>
          <td><select name="nip" id="nip">
          <?php
  if(isset($_POST['nip']))
  {
  $qNip = mysql_query("SELECT * FROM tbl_pegawai WHERE nip = '".$_POST['nip']."'");
  $dtNip = mysql_fetch_array($qNip);
  ?>
    <option value="<?=$dtNip['nip'];?>"><?=$dtNip['nama'];?></option>
          <?php
  }else
  {
  ?>
    <option>-Pilih Penanggung Jawab Pemeliharaan-</option>
          <?php
  }
  ?>
  <?php
  $qNip = mysql_query("SELECT * FROM tbl_pegawai ORDER BY nama ASC");
  while($dtNip = mysql_fetch_array($qNip))
  {
  ?>
    <option value="<?=$dtNip['nip'];?>"><?=$dtNip['nama'];?></option>
  <?
  }
  ?>
          </select>          </td>
        </tr>
        <tr>
          <td>No. SPK/Kuitansi </td>
          <td>:</td>
          <td><input name="no_spk" type="text" id="no_spk" size="50" /></td>
        </tr>
        <tr>
          <td>Tanggal SPK/Kuitansi </td>
          <td>:</td>
          <td><input name="tgl_pemeliharaan" type="text" id="tgl_pemeliharaan" size="10" value="<?=$_POST['tgl_pemeliharaan'];?>" />
          <script language="JavaScript" type="text/javascript">
new tcal ({
// form name
'formname': 'form1',
// input name
'controlname': 'tgl_pemeliharaan'
});
</script></td>
        </tr>
       
        <tr>
          <td align="left" valign="top">Nama Rekanan </td>
          <td align="left" valign="top">:</td>
          <td align="left" valign="top"><input name="nm_rekanan" value="<?=$_POST['nm_rekanan'];?>" type="text" id="nm_rekanan" size="35" /></td>
        </tr>
<tr>
          <td>&nbsp;</td>
          <td>&nbsp;</td>
          <td><input type="submit" name="Submit" value="Simpan" /></td>
        </tr>
  <?php
  if($_POST['Submit']=='Simpan')
  {
  
  // data sudah ada atau belum
$qCr = mysql_query("SELECT id_pemeliharaan FROM tbl_pemeliharaan WHERE tgl_pemeliharaan = STR_TO_DATE('".$_POST['tgl_pemeliharaan']."','%m/%d/%Y') AND id_jenis = '".$_POST['id_jenis']."' AND nm_rekanan = '".$_POST['nm_rekanan']."' AND id_pemeliharaan = '".$_POST['id_pemeliharaan']."'");
$dtCr = mysql_num_rows($qCr);

if($dtCr <= 0)
{
/*
$qId = mysql_query("SELECT id_pemeliharaan FROM tbl_pemeliharaan ORDER BY id_pemeliharaan DESC");
$dtId = mysql_fetch_array($qId);

$id_pemeliharaan = $dtId[0] + 1;
$id_realisasi_anggaran = $dtId[0] + 1;

   $qInsertData = mysql_query("INSERT INTO tbl_pemeliharaan(id_pemeliharaan, id_inventaris, id_jenis, nip, tgl_input, tgl_pemeliharaan, nm_rekanan, no_surat, tgl_surat, asal_surat, no_spk) VALUES('".$id_pemeliharaan."', '".$_POST['id_inventaris']."', '".$_POST['id_jenis']."', '".$_POST['nip']."', CURRENT_DATE(), STR_TO_DATE('".$_POST['tgl_pemeliharaan']."','%m/%d/%Y'), '".$_POST['nm_rekanan']."', '".$_POST['no_surat']."', STR_TO_DATE('".$_POST['tgl_surat']."','%m/%d/%Y'), '".$_POST['asal_surat']."', '".$_POST['no_spk']."')")or die(mysql_error());

include "include/conn_ra.php";
   $qInsertData = mysql_query("INSERT INTO tbl_realisasi_anggaran(thn_anggaran, id_jns_anggaran, kd_program, kd_kegiatan, kd_sub_kegiatan, kd_bas, tgl_realisasi) VALUES('".$_POST['thn_anggaran']."', '".$_POST['id_jns_anggaran']."', '".$_POST['kd_program']."', '".$_POST['kd_kegiatan']."', '".$_POST['kd_sub_kegiatan']."', '".$_POST['kd_bas']."', STR_TO_DATE('".$_POST['tgl_pemeliharaan']."','%m/%d/%Y'))")or die(mysql_error());
*/

$qId = mysql_query("SELECT id_pemeliharaan FROM tbl_pemeliharaan ORDER BY id_pemeliharaan DESC");
$dtId = mysql_fetch_array($qId);
$id_pemeliharaan = $dtId[0] + 1;

include("conn_ra.php");
$kd_sub_sistem = "PMKOM-".$id_pemeliharaan; //kd sub sistem di sistem anggaran

$queryAlokasi = "SELECT alokasi_anggaran FROM tbl_alokasi_anggaran
WHERE thn_anggaran = '".$_POST['thn_anggaran']."' AND id_jns_anggaran = '".$_POST['id_jns_anggaran']."' AND kd_program = '".$_POST['kd_program']."' 
AND kd_kegiatan = '".$_POST['kd_kegiatan']."' AND kd_sub_kegiatan = '".$_POST['kd_sub_kegiatan']."' AND kd_bas = '".$_POST['kd_mak']."' 
AND pj_anggaran = 'Bagian Sistem Informasi'";

$qAlokasi = mysql_query($queryAlokasi);
$dtAlokasi = mysql_fetch_array($qAlokasi);

$queryRealisasi = "SELECT realisasi_anggaran FROM tbl_realisasi_anggaran
WHERE thn_anggaran = '".$_POST['thn_anggaran']."' AND id_jns_anggaran = '".$_POST['id_jns_anggaran']."' AND kd_program = '".$_POST['kd_program']."' 
AND kd_kegiatan = '".$_POST['kd_kegiatan']."' AND kd_sub_kegiatan = '".$_POST['kd_sub_kegiatan']."' AND kd_bas = '".$_POST['kd_mak']."' 
AND pj_anggaran = 'Bagian Sistem Informasi'";

$qRealisasi = mysql_query($queryRealisasi);
$dtRealisasi = mysql_fetch_array($qRealisasi);
$sisaAnggaran = $dtAlokasi['alokasi_anggaran'] - $dtRealisasi['realisasi_anggaran'];

$qInsertAnggaran = mysql_query("INSERT INTO tbl_realisasi_anggaran(thn_anggaran, id_jns_anggaran, kd_program, kd_kegiatan, kd_sub_kegiatan, kd_bas, kd_sub_sistem, 
pj_anggaran, tgl_realisasi) VALUES('".$_POST['thn_anggaran']."', '".$_POST['id_jns_anggaran']."', '".$_POST['kd_program']."', '".$_POST['kd_kegiatan']."', 
'".$_POST['kd_sub_kegiatan']."', '".$_POST['kd_mak']."', '".$kd_sub_sistem."', 'Bagian Sistem Informasi', STR_TO_DATE('".$_POST['tgl_pemeliharaan']."','%m/%d/%Y'))") or die(mysql_error());

mysql_close($link1);

include("conn.php");
/*
$qInsertData = mysql_query("INSERT INTO tbl_pemeliharaan(thn_anggaran, id_jns_anggaran, kd_program, kd_kegiatan, kd_sub_kegiatan, kd_bas, id_pemeliharaan, 
id_kendaraan, id_jenis, nip, tgl_input, tgl_pemeliharaan, nm_bengkel, no_surat, tgl_surat, asl_surat, no_spk, pagu) 
VALUES('".$_POST['thn_anggaran']."', '".$_POST['id_jns_anggaran']."', '".$_POST['kd_program']."', '".$_POST['kd_kegiatan']."', 
'".$_POST['kd_sub_kegiatan']."', '".$_POST['kd_mak']."','".$id_pemeliharaan."', '".$_POST['id_kendaraan']."', '".$_POST['id_jenis']."', '".$_POST['nip']."', 
CURRENT_DATE(), STR_TO_DATE('".$_POST['tgl_pemeliharaan']."','%m/%d/%Y'), '".$_POST['nm_bengkel']."', '".$_POST['no_surat']."', 
STR_TO_DATE('".$_POST['tgl_surat']."','%m/%d/%Y'), '".$_POST['asl_surat']."', '".$_POST['no_spk']."', '".$sisaAnggaran."')") or die(mysql_error());
*/

 if(empty($_POST['thn_anggaran']) OR empty($_POST['id_jns_anggaran']) OR empty($_POST['kd_program']) OR empty($_POST['kd_kegiatan']) OR empty($_POST['kd_sub_kegiatan'])OR empty($_POST['kd_mak'])OR empty($_POST['id_inventaris'])OR empty($_POST['id_jenis'])OR empty($_POST['no_surat'])OR empty($_POST['tgl_surat'])OR empty($_POST['asal_surat'])OR empty($_POST['nip'])OR empty($_POST['no_spk'])OR empty($_POST['tgl_pemeliharaan'])OR empty($_POST['nm_rekanan']))
        {
        echo '<script>alert("Data masih ada yang kosong!");</script>';
        echo '<html><head>
            <meta http-equiv="refresh" content="0;url=index.php?p=tambah_pemeliharaan">
            </head></html>';
        }
        elseif($qInsertData = mysql_query("INSERT INTO tbl_pemeliharaan(thn_anggaran, id_jns_anggaran, kd_program, kd_kegiatan, kd_sub_kegiatan, kd_bas, id_pemeliharaan, id_inventaris, id_jenis, nip, tgl_input, tgl_pemeliharaan, nm_rekanan, no_surat, tgl_surat, asal_surat, no_spk) VALUES('".$_POST['thn_anggaran']."', '".$_POST['id_jns_anggaran']."', '".$_POST['kd_program']."', '".$_POST['kd_kegiatan']."', '".$_POST['kd_sub_kegiatan']."', '".$_POST['kd_mak']."','".$id_pemeliharaan."', '".$_POST['id_inventaris']."', '".$_POST['id_jenis']."', '".$_POST['nip']."', CURRENT_DATE(), STR_TO_DATE('".$_POST['tgl_pemeliharaan']."','%m/%d/%Y'), '".$_POST['nm_rekanan']."', '".$_POST['no_surat']."', STR_TO_DATE('".$_POST['tgl_surat']."','%m/%d/%Y'), '".$_POST['asal_surat']."', '".$_POST['no_spk']."')") or die(mysql_error()))

/*if($qInsertData)
{*/
 ?>{
<script type="text/javascript">
var answer = confirm("Input data berhasil, Lanjutkan ke uraian pekerjaan ?")
if (answer)
{
window.location = "index.php?p=u_pekerjaan&id_pemeliharaan=<?=$id_pemeliharaan;?>";
}
else{
window.location = "index.php?p=pemeliharaan";
}

</script> }
<?
/*}else
{
echo ("<script> alert (\"Input data gagal dilakukan !!\");</script><br>");
echo "<html><head>
<meta http-equiv='refresh' content='0;url=index.php?p=tambah_pemeliharaan'>
</head></html>";
}*/
}
else
{
echo ("<script> alert (\"Data yang dimasukkan sudah ada\");</script><br>");
echo "<html><head>
<meta http-equiv='refresh' content='0;url=index.php?p=pemeliharaan'>
</head></html>";
}

  }
  ?>
     
</form>
      </table>
    </td>
  </tr>
  <tr>
    <td><hr size="1" color="#999999" /></td>
  </tr>
</table>
</body>
</html>

I tried to use ctype_alnum as input validation for the name and the password, so that only letters and numbers are allowed with no spaces.

If I use ctype_alnum only with the nickname, then the nickname will not get entered properly into the database, it will get entered as "1" into the database. And the password does not make it past the elseif statement:


Code: [Select]
        // check password char length
        } elseif (strlen($password) > 25 || strlen($password) < 6) {


Here's the script:

Code: [Select]
/* REGISTER FORM */
// check if submit button has been clicked
if (isset($_POST['submit_signup'])) {

// process and assign variables after post submit button has been clicked
$user_email = strip_tags($_POST['email']);
$user_email             = filter_var($user_email, FILTER_VALIDATE_EMAIL);

$nickname = ctype_alnum(strip_tags($_POST['nickname']));
$password = ctype_alnum($_POST['password']);
$repassword = ctype_alnum($_POST['repassword']);
$month = $_REQUEST['month'];
$day = $_REQUEST['day'];
$year = $_REQUEST['year'];
$dob = $year . "-" . $month . "-" . $day;
$find_us_question = strip_tags(trim($_POST['find_us_question']));

// connect to database
$dbc = mysqli_connect(DB_HOST, DB_USER, DB_PASSWORD, DB_NAME);

$check_query = "SELECT * FROM user WHERE nickname = '$nickname'";

$check_connect  = mysqli_query($dbc, $check_query) or die(mysqli_error($dbc));

$check_count =  mysqli_num_rows($check_connect);

       
       
       
        // Check if the email exists twice
       
        $query_get = "SELECT email FROM user WHERE email = '$user_email'";

        $query_run = mysqli_query($dbc, $query_get);

        $num_rows = mysqli_num_rows($query_run);
       
       
       
       
        if(!$nickname) {
           
            echo 'Please do fill out the name in letters and numbers only, without spaces and special characters.';
           
        } elseif(!$password || !$repassword) {
           
            echo 'Please choose a password which conists of letters and numbers only, without spaces and special characters.';
         
           
        // check if username is already taken   
        }elseif ($check_count != 0) {
           
echo "Username already exists!";
           
               
        } elseif ($num_rows != 0) {
           
            echo "This email address is already registered in the database, you can not register it twice.";
           
           
// check if fields are empty
} elseif (empty($user_email) || empty($nickname) || empty($password) || empty($day) || empty($month) || empty($year)) {

                echo "Please fill out all the fields!";

        // check char length of input data
        } elseif (strlen($nickname) > 30 || strlen($user_email) > 50) {

                echo "Maximum allowed character length for nickname/firstname/lastname are 30 characters!";

        // check password char length
        } elseif (strlen($password) > 25 || strlen($password) < 6) {

                echo "Your password must be between 6 and 25 characters!";

        // check if passwords match with each other
        } elseif ($password != $repassword) {

                echo "Please make sure your passwords are matching!";

        } else {
        // encrypt password
                $password = sha1($password);

        // generate random number for activation process
        $random = rand(1212121212, 9854241752);

        // write into database
Any ideas why I am getting these problems with ctype_alnum() ?