Selecting a select list based on post request - php

Question

please, i'm somewhat new with php bear with me.
I have a selectbox...
<select name="criteria">
<option value="1">Student ID</option>
<option value="2">Firstname </option>
<option value="3">Lastname</option>
<option value="6">All</option>
</select>
<input name="searchvalue" type="text">
<input name="search" type="submit" value="Search">
When i search with a particular option, after the post request, the selected option usually defaults to Student ID. But i want it to still remain the option i searched with. Any suggestion would be appreciated.

Answer 1

To be honest I'd adjust your select code just a little bit to allow for a bit more dynamic editing..
<?php
$options = array('1'=>'Student ID', '2'=>'Firstname', '3'=>'Lastname', '6'=>'All');
?>
<select name="criteria">
<?php
foreach($options as $key=>$value){
$addtItem = '';
if(isset($_POST['criteria']) && $_POST['criteria']==$key){
$addtItem = 'selected="selected"';
}
echo('<option '.addtItem.' value="'.key.'">'.$value.'</option>');
}
?>
</select>
This way you can quickly add more values without a ton of repeat code..

Answer 2

<select name="criteria">
<option value="1" <?php if ($_POST["criteria"] == 1) echo "SELECTED"; ?>>Student ID</option>
<option value="2" <?php if ($_POST["criteria"] == 2) echo "SELECTED"; ?>>Firstname </option>
<option value="3" <?php if ($_POST["criteria"] == 3) echo "SELECTED"; ?>>Lastname</option>
<option value="6" <?php if ($_POST["criteria"] == 6) echo "SELECTED"; ?>>All</option>
</select>
Really ugly, but that works.

Answer 3

You need to check the $_POST array and select the corresponding select item
<?php
$criteria = isset($_POST['criteria']) ? $_POST['criteria']: 0;
?>
<select name="criteria">
<option value="1" <?php echo ($criteria == '1') ? 'selected="selected"': ''; ?>>Student ID</option>
<option value="2" <?php echo ($criteria == '2') ? 'selected="selected"': ''; ?>>Firstname </option>
<option value="3" <?php echo ($criteria == '3') ? 'selected="selected"': ''; ?>>Lastname</option>
<option value="6" <?php echo ($criteria == '6') ? 'selected="selected"': ''; ?>>All</option>
</select>