ansaurus

Question

Need some help with making this function...

Answer 1

A:

You can use Javascript to select an option at runtime, and you can control the Javascript with PHP.

Like this:

<?php $color = $_POST["colors"]; ?>
<script language = "JavaScript">
var colorOption = document.getElementById("<?php print($color)?>");
colorOption.selected = true;
</script>

Just make that script run onLoad, and set each option item's id to its value.

Chetan 2010-01-03 20:24:36

Answer 2

A:

You don't have to completely redo the list with php - just the bit that marks the current choice:

<select name="opts">
<option <?php if(@$_POST['opts'] == 'value1') echo 'selected="SELECTED"'; ?>>value1</option>
<option <?php if(@$_POST['opts'] == 'value2') echo 'selected="SELECTED"'; ?>>value2</option>
</select>

adam 2010-01-03 20:26:25

Answer 3

+2 A:

Sorry to say, but you have to output valid HTML no matter how much of a pain that is. Best suggestion is to wrap it in a helper function and include it. Or even better, go find a good form handling library and use it. This problem has been solved 1000's of times.

XSS CONCERN: Your example code has a number of security flaws. Let me illustrate a simple way to handle a form cleanly. The following code illustrates an error-proof way to handle:

Reading input
Validation
Handling errors, with nice messages
Re-populating the form
Etc...

Please note the use of htmlspecialchars and ENT_QUOTES where needed. Also, the use of the cond ? val1 : val2 operator ensures that there are no E_STRICT warnings omitted, without the use of @ (which can be terrible for performance).

<?php
$FirstName = trim(isset($_POST['FirstName']) ? $_POST['FirstName'] : '');
$LastName = trim(isset($_POST['LastName']) ? $_POST['LastName'] : '');
$Gender = trim(isset($_POST['Gender']) ? $_POST['Gender'] : '');

$Action = trim(isset($_POST['Action']) ? $_POST['Action'] : '');

$Errors = array();

switch($Action)
{
case 'Process':
  // validation code here
  if(empty($FirstName))
  $Errors[] = 'First Name is required.';

  if(empty($LastName))
  $Errors[] = 'Last Name is required.';

  if($Gender != 'Male' and $Gender != 'Female')
  $Errors[] = 'Gender is required.';

  if(count($Errors) > 0)
  $break;

  // save data or whatever here

  // Redirect to next page
  header('Location: nextpage.php');
  exit;
}

?>
<html>
<head>
 ...
</head>
<body>

<?php if(count($Errors) > 0) { ?>
   <div class="error">
      <?php foreach($Error as $e) { ?>
         <p><?php echo htmlspecialchars($e); ?></p>
      <?php } ?>
   </div>
<?php } ?>

<form method="post" action="<?php echo htmlspecialchars($_SERVER['REQUEST_URI'], ENT_QUOTES); ?>">
  <p>
  First Name:
  <input type="text" name="FirstName" value="<?php echo htmlspecialchars($FirstName, ENT_QUOTES); ?>" />
  </p>

  <p>
  Last Name:
  <input type="text" name="LastName" value="<?php echo htmlspecialchars($LastName, ENT_QUOTES); ?>" />
  </p>

  <p>
  Gender:
  <select name="Gender">
    <option value=""></option>
    <option value="Male" <?php if($Gender == 'Male') echo 'selected="selected"'; ?>>Male</option>
    <option value="Female" <?php if($Gender == 'Female') echo 'selected="selected"'; ?>>Female</option>
  </select>
  </p>

</form>

</body>
</html>

gahooa 2010-01-03 20:32:55

Answer 4

A:

How many select boxes and radio buttons does ur form have. If the count is less than 10 u can use javascript and make it easily. Else its recommended to make your select boxes in php

PHP CODE :

<?php

$color = $_POST["colors"];
$colors = array("red","green","blue");

?>
<select name="colors">

<?php 
$varSelected = "";
foreach ($colors as $option) 
{ 

  if($option == $color)
  {
    $varSelected = "selected:selected";
  }
  else
  {
    $varSelected ="";
  }
?>
  <option <?php echo $varSelected?>>
    <?php print $option; ?>
  </option>

<?php 
} 
?>
</select>

Javasript Method : Will need form modification. You will have to add id to your option boxes which will be same as its value.

// supposing $_POST['colors']='Red';
<html>
<select name="gender">
<option value="Red" id="Red">Red</option>
<option value="Blue" id="Blue">Blue</option>
</select>
</html>

<script type="text/javascript">
document.getElementById("<?php echo $_POST['colors']").setAttribute("selected", "selected");
</script>

Zaje 2010-01-03 20:59:22

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Need some help with making this function...

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