isset function stopped working

Hi

The isset function has seemed to have stopped working in a few of my scripts. The example below shows it used in a form when the form is posted. The global variables used within the function seem to be blank (almost like the isset function clears any values they have). I have tried echoeing out the variables before the function and the correct values are printed to the screen. The code is as follows:

<select name = "add_student" id = "add_student">
		<?php while ($row = mysql_fetch_assoc($rst)) 
		{ 
			$individual = $row['PU_Surname'] . " " . $row['PU_Forename'] . " - " . $row['PU_AdNo'];	
		?>
			<option value="<?php echo $row['PU_AdNo']; ?>"><?php echo $individual; ?></option>
		<?php } ?>
		</select>
		</td>
		<td>
			&nbsp;&nbsp;&nbsp;&nbsp;
		</td>
		<td>
			<input type="submit" name="Submit" value="Submit" onclick = 'javascript: return confirm("Are you sure you want to add this student to this class?")' />
			<input type = 'hidden' name = 'submitted' value = 'true'>
		
		</td>
	</tr>
</table>
</form>
<?php 
	$ad_no = $_POST['add_student'];
	
	if (isset($_POST['add_student'])) 
		{
			echo $row['PU_AdNo'];
		 	$sql3 = "INSERT INTO ClassStudent ( CS_CL_ClassName , CS_PU_AdNo , CS_CL_SubjectCode , CS_PU_Year, CS_GT ) VALUES ('" . $current_class . "', '" . $ad_no . "', '" . $subjectcode . "', '" . $current_year . "', '" . $current_year . "')";
			
			include("../includes/php/connect3.php");
		}
?>

HTML:

The INSERT statement does work, but the $current_class, $subjectcode and $current_year variables are blank when they should contain values.

Any help with this issue would be greatly appreciated.

 

It seems you have register_globals turned OFF (and it's good). Instead of using autoglobals ($current_class) use values from $_POST ($_POST('current_class']).

 

Your brackets don't make sense.

 

You are assigning $ad_no to the $_POST before you check if that $_POST is set, change that around, check if that post isset first then assign it. Also, what are you using in your main form tag, $_SERVER['PHP_SELF'] ? Also, what does the include do at the very bottom?

<select name = "add_student" id = "add_student">
     <?php 
      while ($row = mysql_fetch_assoc($rst))
       {
            $individual = $row['PU_Surname'] . " " . $row['PU_Forename'] . " - " . $row['PU_AdNo']; 
        ?>
            <option value="<?php echo $row['PU_AdNo']; ?>"><?php echo $individual; ?></option>
        <?php 
        } ?>
</select>
</td>
<td>
     &nbsp;&nbsp;&nbsp;&nbsp;
</td>
<td>
       <input type="submit" name="Submit" value="Submit" onclick = 'javascript: return confirm("Are you sure you want to add this student to this class?")' />
       <input type = 'hidden' name = 'submitted' value = 'true'>
</td>
</tr>
</table>
</form>
<?php
$ad_no = '';
if (isset($_POST['add_student']))
{
     $ad_no = $_POST['add_student'];
     echo $row['PU_AdNo'];
     $sql3 = "INSERT INTO ClassStudent ( CS_CL_ClassName , CS_PU_AdNo , CS_CL_SubjectCode , CS_PU_Year, CS_GT ) VALUES ('" . $current_class . "', '" . $ad_no . "', '" . $subjectcode . "', '" . $current_year . "', '" . $current_year . "')";
           
            include("../includes/php/connect3.php");
        }
?> 

Code (markup):

 

use empty()