problem passing values in error checking

[mcrumlish]

Hi,

I am working on a survey application. A user fills in different questions and submits the survey. At the moment I am working on error checking. I am doing this in PHP rather than javascript.

The way the survey is set up, it is split into different pages with a number of questions on each page. If, for example, a user is on a page with 5 questions and they only complete 4 then they will get an error message and the same 5 questions will be output. These questions are all created dynamically and are named like this:

echo '<input type="radio" name="answer[',$qid,']" value="',$q1r['aid'],'"'; 

$qid and $q1r are values from a DB. The reason each question is named like answer[$qid] is to do with the way I insert them into the database. I loop through the HTTP_POST_VARS array with a foreach looking for every element in the 'answer' array.

When a user hits submit the error checking checks the number of passed values against the number of questions on the previous page. If this number is less than the number of questions then there is an error and the p[revious questions are loaded again. What I need to do is to make any of the questions that were completed, still maintain there values.

In pseudo code it is like this:

if(radio_button_value == question_variable_value_from_prev_page){ echo selected';
} 

Any help with this is appreciated.

Thanks,
Martin

[Mandibal]

You could just use sessions to pass the variables back.
On your error checking store the answers in $_SESSION['answers'] (or something similar). Make sure of course to put session_start() at the top of the error checking page and the form page. In the form page you can just do:

if ($_SESSION['answer'] == radio_button_value){ echo selected;
} 

[Gaheris]

Is this what you're looking for?

function get_checked_answer($_qid, $_aid)
{
    return ($_POST['anser'][$_qid] == $_aid) ? 'checked="checked"' : ''; 
}

echo '<input type="radio" name="answer[',$qid,']" value="',$q1r['aid'],'" ',get_checked_answer($qid, $q1r['aid']),' />'; 

[mcrumlish]

I tried that code but it didn't work.

The value I want to check is the value that is passed from the previous page and I need to check this against the $q1r['aid'] so if i used the variable $qid that wouldnt work as that is just defined in my script from a DB entry. it is the ID of each question.

I have managed to get it working for radio buttons, it was simpler than i thought:

if($answer[$qid] == $q1r['aid']){echo ' checked><br>',"\n";}else{echo "><br>\n";} 

However, it would be better if i could do this in a function.

The part I am having a problem with now is with checkboxes. Any idea how I could get that working?

[Gaheris]

Well, I almost had the code correct, I just wasn't sure where the variables came from.

Can you post some sample check box markup, please?

[mcrumlish]

Here's my code for checkboxes:

    if($qrow['qtype'] == "checkbox"){
        $qid = $qrow['qid'];
        $q1 = "SELECT * FROM answers WHERE sid = '$sid' AND qid = '$qid'";
        $r1 = mysql_query($q1) or die(mysql_error());
        echo "<br>";
        $totalarr = mysql_num_rows($r1);
        while($q1r = mysql_fetch_array($r1)){
            echo $q1r['answer'].' - <input type="checkbox" name=answer[',$qid,'][] value="',$q1r['aid'],'"';
            $arrcount = 0;
            while($arrcount < $totalarr){
                if($answer[$qid][$arrcount] == $q1r['aid']){echo ' checked';}else{echo "";}
                $arrcount++;
            }
            echo "><br>\n";

        }//end checkbox loop
        echo "<p>\n";
    }//end if checkbox type question 

This sort of works but i am pretty sure there is a much better way of doing it! At the moment if i fill in 1 checkbox item and leave another question 9ie radio button) blank then it keeps the checkbox value. However, in this page if I decide I want to tick another checkbox it starts acting strangely and doesn't work or checks the wrong box.

Thanks,
Martin