Created on 23/01/2008 14:59 by Tobias Tom

<?php
 
function validate_extension( $filename, $validExtensions = array() )
{
	// if no extensions given, use the default ones
    if ( empty( $validExtensions ) ) {
        $validExtensions = array('zip', 'rar', 'jpg', 'jpeg', 'gif',
'bmp');
    }
 
	// find the last dot inside the filename
    $dotPos = strrpos( $filename, '.' );
	// if no dot was found, the extension is not valid
    if ( false === $dotPos ) { return false; }
 
	// get the extension, be sure the dot is not included, and be sure
the
	// string gets to lowercase
    $extension = substr( $filename, ( $dotPos + 1 ) );
    $extension = strtolower( $extension );
 
	// when the extension is inside the array, it is valid
    return in_array( $extension, $validExtensions );
}