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Question

So I made this car statistics calculation module, which after doing some calculations returns to show the results and then show the car I've jsut calculated for as the pre-selectedon in my form.

For this I made a function in php, I could use within my html:

function biler () {                         
    while($row = mysql_fetch_array($result)) {
       if ($row['reg'] == $_GET['bil']){
           $selected = 'selected="selected"';
       }                    
       echo '<option '.$selected.' value="'.$row['reg'].'">'.$row['reg'].'</option>';
    }
}

The HTML in which the functions run:

<form method="post" name="regnskab" action="regnskab_beregn.php">
   <select name="bil"><? biler(); ?></select>
</form>

My problem is that the is no car pre selected, because they all have the select statement :/

Returns:

<select name="bil">
  <option selected="selected" value="OHO1241">OHO1241</option>
  <option selected="selected" value="QTX2314">QTX2314</option>
  <option selected="selected" value="QW20301">QW20301</option>
</select>

Answer 1

You need to clear the $selected variable after using it otherwise it will always contain that value:

while($row = mysql_fetch_array($result)) {
   $selected = "";
   if ($row['reg'] == $_GET['bil']){
       $selected = 'selected="selected"';
   }                    
   echo '<option '.$selected.' value="'.$row['reg'].'">'.$row['reg'].'</option>';
}

Answer 2

Once your $selected is set, it still exists. My example

    function biler () {                         
        while($row = mysql_fetch_array($result)) {
           if ($row['reg'] == $_GET['bil']){
               $selected = 'selected="selected"';
           }          
           else
           {
               $selected = "";
           }          
           echo '<option '.$selected.' value="'.$row['reg'].'">'.$row['reg'].'</option>';
        }
    }