How to get a subset of $_POST array with keys starting with a prefix

Question

Let\'s say my $_POST variable looks like:

 65
    [action] => editpost
    [originalaction] => editpo         


        

Answer 1

Here's a cool ultra-php-neat way to use php array_walk to specify a generic prefix to remove:

$foo = array('k_foo' =>"bar", 
              'k_bar' =>"b0r", 
              'y_foo' =>"b5r",
              'y_not' =>"b7r", 
             'k_not' =>"b1r");

$subsetArray = $foo;
$key_prefix = "k_";

array_walk($foo, 'removeUnwanted', array(&$subsetArray, $key_prefix));
var_dump ($subsetArray);

function removeUnwanted($value, $key, $array){
    $prefix = $array[1];
    $testArray = &$array[0];
    if(strpos($key,$prefix) ===0){
        unset($testArray[$key]); 
    } 
}

Now you can just call array walk, with a copy of the array of values, and the prefix string.