Displaying Select on GET - php

Question

If I have a select form, for example:
<form action='?' method='get' name='form_filter' class="sortoptions" >
<select name="sort" >
<option value="None">None</option>
<option value="PriceLow">Price (Low to High)</option>
<option value="PriceHigh">Price (High to Low)</option>
<option value="NameAZ">Name (A-Z)</option>
<option value="NameZA">Name (Z-A)</option>
</select>
I'm submitting using the GET method but need a way of when its been submitted and on the results page the option which was selected to be displayed.
So say if 'Price (High to Low)' is selected it will then be displayed in the select box on the results page after its been submitted
Any ideas?
Thanks!

Answer 1

When you will submit the form (assuming there is a submit button in your form), all data will be sent to PHP and you will retrieve all your data inside $_GET (the global var)
$_GET['sort']
will contain the value selected.
Then if you want to pre select, you just have to add some PHP code inside your HTML
<option value="PriceLow" <?php echo ((!empty($_GET['sort']) && $_GET['sort'] == 'PriceLow') ? 'selected="selected"' : '') ?>>Price (Low to High)</option>
You have to do the same for each option of the select.
That will allow you to preselect the good option after a first submit.
Solution 2:
If you don't wan to insert too much PHP inside your HTML code, you can store the posted value inside a javascript var and then, select the good option when the DOM is loaded (using a good JS library like jQuery for example)
Your HTML code:
<select name="sort" >
<option value="None">None</option>
<option value="PriceLow">Price (Low to High)</option>
<option value="PriceHigh">Price (High to Low)</option>
<option value="NameAZ">Name (A-Z)</option>
<option value="NameZA">Name (Z-A)</option>
</select>
And some JS code in <script> tag
// Need jQuery !
$(document).ready(function() {
// Generate the selected var in JS using the value in PHP
var selectedOption = '<?php echo $_GET['sort']; ?>';
// Select the selected option and append the selected attribute
$("select[name=sort] option[value=" + selectedOption + "]").attr('selected', 'selected');
});
This code will automatically select the good option once the page is loaded.
Info: The good point is that you have a more clear and maintanable HTML code. The bad point is that if JavaScript is not enabled on the client, your automatic selection will not work (it will always work when you are using PHP to add "selected" in HTML). So you have to evaluate pro and cons and make your choice.
Note: you can leave the action empty instead of "?"

Answer 2

$_GET['sort']
in the submitted page will give you the selected option. And to check whether the form has been submitted:
if(isset($_GET['submit'])) {
// do something with the result
}
where 'submit' is the name of your submit button.

Answer 3

Try this code, it's probably what you would want. I assume you're writing it in your .php files or your other extensions, perhaps .html have php code enabled in them (maybe via .htaccess file)
<?php if (isset($_GET['sort'])){ ?>
<?php $sel= $_GET['sort']; # format? ?>
<strong><?php print($sel);?></strong>
<?php } ?>
<form action='' method='GET' name='form_filter' class="sortoptions" >
<select name="sort" >
<?php
$ff = Array(
'None' => 'None',
'PriceLow' => 'Price (Low to High)',
'PriceHigh' => 'Price (High to Low)',
'NameAZ' => 'Name (A-Z)',
'NameZA' => 'Name (Z-A)',
);
?>
<?php foreach ($ff as $v => $t) {?>
<option value="<?php print($v);?>" <?php if (isset($_GET['sort']) && ($_GET['sort'] == $v)) print('selected="selected"');?>"><?php print($t);?></option>
<?php } ?>
</select>
<input name="submit" type="submit" />
</form>