Quick question about creating a basic grading system... please help asap

So I am building a quick online testing system. I have it setup so I can create multiple choice questions (all questions have exactly 4 answers), save the questions, answers, and the correct answer in mysql db, and have it randomly show 25 questions form the database on the actual testing page. I am stuck on how to actually get the results of what they click on.

This is the code to show the questions on the test page.

Code:

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$result8 = mysql_query("SELECT * FROM sampletest ORDER BY RAND() LIMIT 25");
while($row8 = mysql_fetch_assoc($result8)) {
 
  echo "<table width='200' border='0' cellpadding='0' cellspacing='0'>
      <tr>
        <td><div align='center'>";
        echo $row8['question'];
        echo "</div></td>
      </tr>
      <tr>
        <td> <p align='center'>
      <label>
        <select name='";
        echo $row8['id'];
        echo "' size='5' id='";
        echo $row8['id'];
        echo "'>
          <option value='";
        echo $row8['a'];
        echo "'>";
        echo $row8['a'];
        echo "</option>
          <option value='";
        echo $row8['b'];
        echo "'>";
        echo $row8['b'];
        echo "</option>
          <option value='";
        echo $row8['c'];
        echo "'>";
        echo $row8['c'];
        echo "</option>
          <option value='";
        echo $row8['d'];
        echo "'>";
        echo $row8['d'];
        echo "</option>
        </select>
        </label>
      <br /><hr>
    </p></td>
      </tr>
    </table>";
       
                }

---

But I don't understand how I would get the actual grading page to determine whether they have selected the correct answer for each unique question id.

Any more info I can give and I will.

I think you'd have to create another table in the database with all the correct answers and the corresponding question id. Then on the final page do a lookup and see if they got it right or not.

http://www.php.net/manual/en/faq.htm...aq.html.arrays

Code:

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<select name="questions[523]">
  <option value="a">...</option>
  <option value="b">...</option>
  <option value="c">...</option>
  <option value="d">...</option>
</select>
<select name="questions[199]">
  <option value="a">...</option>
  <option value="b">...</option>
  <option value="c">...</option>
  <option value="d">...</option>
</select>

---

The 523 and 199 would be your unique question ids. I'm assuming they are integers.

PHP Code:

---

// print_r($_POST['questions']);

$question_ids = implode(',', array_map('intval', array_keys($_POST['questions'])));

$sql = "
SELECT question_id
     , answer_code
  FROM questions
 WHERE question_id IN ($question_ids)
"; 


---

PHP Code:

---

while ($row = mysql_fetch_assoc($res)) {
    if ($row['answer_code'] === $_POST[$row['question_id']]) {
        //correct
    } else {
        // wrong
    }
} 


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