Hello everyone! I am a student and I am currently working for online voting system for my school. I am having a hard time how to prevent users/students from multiple votes. Could please give me some example that users can only vote once using their ID number? I have a login system. I know there is a lot of tutorial out there but mostly they used IP address. Any help would be greatly appreciated. This is my code so far:
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<form action="candidates.php" method="post">
<?php
include('voting_connect.php');
{
$result = mysql_query("SELECT * FROM candidates WHERE c_position='President'")
or die(mysql_error());
echo "<center><table id='tables' class='sortable'>";
echo "<tr><th scope='col' abbr='' class='nobg'> </th> <th>President:</th></tr>";
while($row = mysql_fetch_array($result))
{
echo "<tr>";
echo "<td scope='row' class='spec'>" . '<input name="selector[]" type="radio" value="'.$row['c_ID'].'">' . "</td>";
echo "<td>";
echo '<a href=# alt=Candidate Profile rel=tooltip content="<div id=imagcon><img src='.$row['c_Location'].' class=tooltip-image/></div><div id=con>Running for:'.$row['c_position'].'</div><div id=con>Gender:'.$row['c_gender'].'</div><div id=con>Year:'.$row['c_Year'].'</div><div id=con>Course:'.$row['c_Course'].'</div><div id=con>Class:'.$row['c_Class'].'</div><div id=con>Partylist:'.$row['c_Partylist'].'</div>">'.$row['c_fname'].' '.$row['c_lname'].'</a>'.'<br>';
echo "</td>";
echo"</tr>";
}
echo"</table></center>";
}
?>
<br></br>
<?php
include('voting_connect.php');
{
$result = mysql_query("SELECT * FROM candidates WHERE c_position='Vice President'")
or die(mysql_error());
echo "<center><table id='tables' class='sortable'>";
echo "<tr><th scope='col' abbr='' class='nobg'> </th> <th>Vice President:</th></tr>";
while($row = mysql_fetch_array($result))
{
echo "<tr>";
echo "<td scope='row' class='spec'>" . '<input name="selector1[]" type="radio" value="'.$row['c_ID'].'">' . "</td>";
echo "<td>";
echo '<a href=# alt=Candidate Profile rel=tooltip content="<div id=imagcon><img src='.$row['c_Location'].' class=tooltip-image/></div><div id=con>Running for:'.$row['c_position'].'</div><div id=con>Gender:'.$row['c_gender'].'</div><div id=con>Year:'.$row['c_Year'].'</div><div id=con>Course:'.$row['c_Course'].'</div><div id=con>Class:'.$row['c_Class'].'</div><div id=con>Partylist:'.$row['c_Partylist'].'</div>">'.$row['c_fname'].' '.$row['c_lname'].'</a>'.'<br>';
echo "</td>";
echo"</tr>";
}
echo"</table></center>";
}
?>
<br></br>
<?php
include('voting_connect.php');
{
$result = mysql_query("SELECT * FROM candidates WHERE c_position='Secretary'")
or die(mysql_error());
echo "<center><table id='tables' class='sortable'>";
echo "<tr><th scope='col' abbr='' class='nobg'> </th> <th>Secretary:</th></tr>";
while($row = mysql_fetch_array($result))
{
echo "<tr>";
echo "<td scope='row' class='spec'>" . '<input name="selector2[]" type="radio" value="'.$row['c_ID'].'">' . "</td>";
echo "<td>";
echo '<a href=# alt=Candidate Profile rel=tooltip content="<div id=imagcon><img src='.$row['c_Location'].' class=tooltip-image/></div><div id=con>Running for:'.$row['c_position'].'</div><div id=con>Gender:'.$row['c_gender'].'</div><div id=con>Year:'.$row['c_Year'].'</div><div id=con>Course:'.$row['c_Course'].'</div><div id=con>Class:'.$row['c_Class'].'</div><div id=con>Partylist:'.$row['c_Partylist'].'</div>">'.$row['c_fname'].' '.$row['c_lname'].'</a>'.'<br>';
echo "</td>";
echo"</tr>";
}
echo"</table></center>";
}
?>
<br />
<br />
<input type="submit" value="Vote!" name=submit"/>
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