php颜色转换函数hex-rgb(将十六进制格式转成十进制

<?php  
 function hex2rgb($colour) {  
    if ($colour [0] == '#') {  
        $colour = substr ( $colour, 1 );  
    }  
    if (strlen ( $colour ) == 6) {  
        list ( $r, $g, $b ) = array ($colour [0] . $colour [1], $colour [2] . $colour [3], $colour [4] . $colour [5] );  
    } elseif (strlen ( $colour ) == 3) {  
        list ( $r, $g, $b ) = array ($colour [0] . $colour [0], $colour [1] . $colour [1], $colour [2] . $colour [2] );  
    } else {  
        return false;  
    }  
    $r = hexdec ( $r );  
    $g = hexdec ( $g );  
    $b = hexdec ( $b );  
    return array ('red' => $r, 'green' => $g, 'blue' => $b );  
}  
$b = hex2rgb ( "#ff0" );  
print_r ( $b );  
?>