[SOLVED] for loop help

[plastik77]

Hi, I'm having a problem trying to work out how to process arrays passed from an HTML form. This is probably due to my lack of PHP experience, but any help would be appreciated. I have a form where the user can enter a range of possible answers to a multiple choice question. For each text field there is also a radio button, which indicates which of the options is the correct answer. I've managed to get this to work using a cumbersome approach, however I really should be using arrays to make it more efficient. I need to insert the question text into a database while also checking the corresponding radio button to see whether or not it is checked as the correct answer. I have labelled the radio buttons with values corresponding to the index of each element in the answers[] array. I therefore need to process the form in a loop which allows me to track the index of each element in the array. A standard for loop using $i as an index would be how I would like to do this, but I am not sure if I can do this in PHP (the foreach loop doesn't seem as it would let me track the index).

 

Here is the HTML form....

 

<form action="<? $_SERVER['PHP_SELF'] ?>" method ="post" id="questSubmit">

Enter the answer options and ensure the radio button selected is the correct answer. <br/><br/>

<input type="radio" name="option" value="0"/> A: <input type="text" name="answer[]" size="80"/><br/><br/>

<input type="radio" name="option" value="1" /> B: <input type="text" name="answer[]" size="80"/><br/><br/>

<input type="radio" name="option" value="2" /> C: <input type="text" name="answer[]" size="80"/><br/><br/>

<input type="radio" name="option" value="3"/> D: <input type="text" name="answer[]" size="80"/><br/><br/>

<input type="radio" name="option" value="4" /> E: <input type="text" name="answer[]" size="80"/><br/><br/>

<input type="radio" name="option" value="No Answer" checked="checked" />No Answer selected

<input name="SubmitNext" value="Save and add another question" type="submit" title="Submit" /><br/><br/>

<input name="SubmitProceed" value="Save and proceed to next stage" type="submit" title="Submit" />

</form>

 

and here's the PHP i have so far - the for loop i've used doesn't actually work...

 

if (isset($_POST['SubmitNext']))

 

{

$correct = $_POST['option'];

echo $correct;

 

$answers = array($_POST['answer']);

echo count($answers);

 

for($i=0;$i<count($answers);$i++)

echo $answers[$i];

 

}

 

[deadimp]

Your problem is this line of code:

$answers = array($_POST['answer']);

That would make an array, with the first and only element being the value of $_POST['answer'], another array, which will make $answer a multi-dimensional array. I'm guessing that your thought process right there was that you had to cast the POST data to an array - PHP takes the data as it is, meaning that $_POST['answer'] is already an array.

I also see that you're trying to associate the options with the answer, but the way you've done it, there's a change that something could come along and screw it up. Since you're going to connect the two, manually index your input's name.

Example:

//Generate form
$count=5;
$name=array("A","B","C","D","E"); //Yeah, this was cheap. Change this later.
for ($i=0;$i<$count;$i++) {
echo "<input type='radio' name='option' value='$i'>$name[$i] <input type='text' name='answer[$i]' size='80'><br>";
}

//Check submit
if (key_exists("answer",$_POST)) {
$answer=array();
foreach ($_POST["answer"] as $i => $value) { //Indexing too
  if ($_POST["option"][$i]) echo "[] "; //Correct answer
  echo "$value<br>";
}
}

 

Is this for a test generator?

[plastik77]

many thanks deadimp - that's a much better and more efficient way of doing it than i had previously. yes it is for a test generator - this is a small part of a large form but probably the trickiest part of it. i changed the code a little to the following as the if ($_POST["option"][$i]) line was giving me a problem. hadn't come across key_exists before either so that's useful for the future -

 

//test to see which is the correct answer

if ($_POST["option"]==$i)

{

    $corr = "yes";

    $query2 = "insert into Answer values ('$id','$opt','$value','$corr')";

    $result2 = mysql_query($query2);

    if (!$result2)

echo "Invalid Insert information";

}