Matt Lowden

Recovering HTTP $_GET variables when using Apache’s mod_rewrite

Matt — Thu, 13 May 2010 12:43:26 +0000

Anyone using Apache’s mod_rewrite to handle HTTP requests will know that your $_GET variables are no longer recognised by the server as the URI is treated as a single string value.

PHP has a function, called mb_parse_str(), that parses the query string representation of an array into a multi-dimensional array. This can be used to correctly represent the query string part of the URL.

The below function returns an array that holds the same values you’d expect from $_GET.

function get_http_vars(){
  $query = parse_url($_SERVER['REQUEST_URI'], PHP_URL_QUERY);
  mb_parse_str($query, $get);
  return $get;
}

To use the function simply follow the example below;

$get = get_http_vars();

Deep merging two arrays in PHP

Matt — Thu, 04 Feb 2010 13:22:18 +0000

PHP has a wealth of functions for manipulating arrays, however; I often want to deep merge 2 arrays whilst maintaining the key => value structure. PHP does have functions that will merge multiple arrays but they attempt to maintain duplicate keys.

The below function take 2 arguments (arrays). Arguments are in order of importance, the second arguments values will always overwrite the first arguments values and so on.

function array_merge_replace($base_array, $merge_array){
	$new_array = array();
	$key_list = array_merge((array)$base_array, (array)$merge_array);
	foreach($key_list as $k=&gt;$v){
		if(is_array($base_array[$k])||is_array($merge_array[$k])){
			$new_array[$k] = array_merge_replace($base_array[$k], $merge_array[$k]);
		}else{
			$new_array[$k] = $merge_array[$k] ? $merge_array[$k] : $base_array[$k];
		}
	}
	return $new_array;
}

Removing null values from a PHP Array

Matt — Wed, 29 Jul 2009 12:00:58 +0000

The following function will remove all null values from a PHP array. This is especially useful when exploding strings with a post/prefixed delimiter.

function array_remove_null(&amp;$array){
	$new_array = array();
	foreach($array as $k=&gt;$v){
		if($v) $new_array[$k]=$v;
	}
	$array=$new_array;
}

To use the function simply follow the example below;

array_remove_null($your_array_object);

Auto-hide field prompt

Matt — Mon, 06 Apr 2009 21:34:47 +0000

Recently I’ve developed a couple of forms that prompt user input via the value of the field rather than a label. For instance, the text “Enter your name” within a field that requires you to enter your name.

Usually I want the text to disappear when the user focuses on the input or textarea element and reappear if the user moves away from the the element without inputting any text.

This function looks for all input and textarea elements with the class “hide-prompt”. Simply run this function after the DOM has loaded. Make sure that your input and textarea elements have unique ID’s.

jQuery

function _field_value_prompt(){
	var field_list = $('input.hide-prompt, textarea.hide-prompt');
	var field_list_values = Array();
	for(var f=0; f &lt; field_list.length;f++){
		field_list_values[$(current_element).attr('id')] = $(current_element).val();
	}
 
	$(field_list).focus(function(){
		if($(this).val() == field_list_values[$(this).attr('id')]){
			$(this).val('');
		}
	});
 
	$(field_list).blur(function(){
		if($(this).val() == ''){
			$(this).val(field_list_values[$(this).attr('id')]);
		}
	});
}