Form Validation

[steve m]

Hi there,

I've been trying to come up with a way to validate a form. I came up with this below, but I'm sure there is a more efficient way to do this. I am just writing IF statements and if the statement is true I will assign a variable to a background color in the input field. Is there a more efficient way to do this? Or am I going about this the wrong way?

<?php
//$disply_button is the submit button
if(isset($disply_button)){
$bgcolor = "";
if ($model_number == ""){
$bgcolor1 = "background-color: red;";
}
if ($serial_number == ""){
$bgcolor2 = "background-color: red;";
}
if ($misc == ""){
$bgcolor3 = "background-color: red;";
}

include("closerma3.php");
}
?>

Below is the HTML code from closerma3.php. Where the variables will be displayed

<tr>
<td height="28" width="205">Model:
<input style="<?php echo $bgcolor1; ?>" type="text" name="model_number"onchange="convertField()"
size="20" tabindex="4" value="<?php echo $model_number; ?>">
</td>
<td height="28" width="212"><b>Serial:</b>
<input style="<?php echo $bgcolor2; ?>" type="text" name="serial_number" onchange="convertField()"
size="20" tabindex="5" value="<?php echo $serial_number; ?>">
</td>
<td height="28" width="198">Misc:
<input style="<?php echo $bgcolor3; ?>" type="text" name="misc" onchange="convertField()"
size="15" tabindex="6" value="<?php echo $misc; ?>">
</td>
</tr>

[kenrbnsn]

I use a select statement to check the fields and store error messages and/or css color changes in arrays. Also, make sure you don't depend on register_globals being set. In the following code, I'm assuming that your form is using method "POST".
[code]<?php
$errs = array();
if(isset($_POST['disply_button'])){
      foreach($_POST as $k => $v)
           switch($k) {
                  case 'model_number':
                  case 'serial_number':
                  case 'misc':
                          if (trim($v) == '') $errs[$k] = 'style="background-color:red"';
                          break;
             }
}
?>[/code]

And also change your included file:
[code]<?php
$rows = array('model_number' => array('w' => 205, 's'=>20),
                     'serial_number' =>   array('w' => 212, 's'=>20),
                     'misc' => array('w' => 198, 's' => 15));
$tab_index = 4;
$tmp = array();
foreach ($rows as $k => $ary) {
    $x = explode('_',$k);
    $tmp[] = '<td height="28" width="' . $ary['w'] . '">' . ucwords($x[0]) . ': ';
    $style = (isset($errs[$k]))?$errs[$k]:'';
    $tmp[] = '<input ' . $style . ' type="text" name="' . $k . '" onchange="convertField()" size="' . $ary['s'] . '" tabindex="' . $tab_index++ . '" value="' . trim(htmlentities($_POST[$k])) . '">';
}
echo "<tr>\n" . implode("</td>\n", $tmp) . "</td>\n</tr>\n";
?>[/code]

Ken