Checking Input

[Ratneer]

So basically I have a site, and on that site, I have a page that submits a form and updates a database. I have it set up so that someone can enter in Multiple values into a textarea, one on each line, and it will submit each of those values as a new row in the database, but for the life of me, I cannot figure out how to check those values against the actual users.

 

It is basically a point system, where the staff can award points users of the site. But at the moment, a Staff member could enter in Jibberish, and it would insert that into the database, but I want it to check my users table to make sure the user exists before it inserts it into the database.

 

here is my code:

<?php
include 'global.php';

echo $headersidebar;


if ($_COOKIE['access'] == $accessstaff)
{





if(count($_POST))
{



$array = preg_split('/(\r?\n)+/', $_POST['studentname']);
foreach($array as $students)
   {
   
   $statusmsg = '<center><span style="background: #A6FF9E;">You have successfully submitted points to the database.</span></center>';
   
   mysql_query("INSERT INTO points (giver, receiver, points, category, reason, date, status) VALUES ('{$_COOKIE['username']}', '{$students}', '{$_POST['pointamt']}', '{$_POST['pointcat']}', '{$_POST['pointreason']}', '{$date}', 'Validating')");
   }
}


$addpointspage = $statusmsg . '



<form action="submit_points.php" method="post">



<table class="table" >



<tr>



<td colspan="10">



<h1><strong><center>Submit Points</center></strong></h1>



</td>



</tr>



<tr>



<td colspan="10" rowspan="100">



<center>Please remember to follow the house point limits when submitting house points.</center>



</td>



</tr>



</table>






<table class="table">






<tr>



<td style="width: 15%;" valign="top">



Student Name:<br> <span style="font-size: 60%;">(List as many as you want; One per Line)</span>



</td>



<td colspan="10">



<center><textarea name="studentname" cols="60" rows="10"></textarea></center>



</td>



</tr>






<tr>



<td style="width: 15%;" valign="top">



Amount of Points:



</td>



<td>



<input style="position: relative; left: 16px;" type="text" size="15" name="pointamt" />



</td>



<td>



Do not put anything that is not a number into this box.



</td>



</tr>






<tr>



<td style="width: 15%;" valign="top">



Point Category:



</td>



<td colspan="10">



<select name="pointcat" style="position: relative; left: 16px;">






<option SELECTED value="">-------</option>



<option>Class Work</option>



<option>Class Exam</option>



<option>Extra Work</option>



<option>Contests</option>



<option>Teacher\'s Assistant</option>



<option>Negative Points</option>






</select>



</td>



</tr>






<tr>



<td style="width: 15%;" valign="top">



Reason:



</td>



<td colspan="10">



<input style="position: relative; left: 16px;" name="pointreason" type="text" size="80" />



</td>



</tr>






<tr>



<td>



</td>



<td colspan="10">



<input style="position: relative; left: 16px;" type="submit" value="Submit Points" />



</td>



</tr>















</table



</form>



';

}

elseif (1==1)
{
$addpointspage = $accessdenied;
}



echo



'





<!-- start content -->





<div id="content">







<div class="post">









<div class="entry">











<p><strong>' . $addpointspage . '</p>











<p class="links">' . $addpointslink . '</p>









</div>







</div>





</div>





<!-- end content -->





<div style="clear: both;"> </div>



</div>



<!-- end page -->
</div>';








echo $footer;





?>

 

 

I am fairly new to PHP, so I would appreciate any help someone could give me; I am not too good with arrays and such, so this one has got me stumped.

[Ratneer]

I tried run a SELECT query to return the row of my users from my database, and then if something like if ($row['username'] != $array['inputtedusername']) but it didn't do anything, I guess I did something wrong with the array. Someone Please help.