php Hex RGB颜色值互换的使用

function HexToRGB($colour) {
if ($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 ( $r,$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' => $b
);
}
function RGBToHex($rgb) {
$regexp = "/^rgb(([0-9]{0,3}),s*([0-9]{0,3}))/";
$re = preg_match ( $regexp,$rgb,$match );
$re = array_shift ( $match );
$hexColor = "#";
$hex = array (
'0',
'1',
'2',
'3',
'4',
'5',
'6',
'7',
'8',
'9',
'A',
'B',
'C',
'D',
'E',
'F'
);
for($i = 0; $i < 3; $i ++) {
$r = null;
$c = $match [$i];
$hexAr = array (); while ( $c > 16 ) {
$r = $c % 16;
$c = ($c / 16) >> 0;
array_push ( $hexAr,$hex [$r] );
}
array_push ( $hexAr,$hex [$c] ); $ret = array_reverse ( $hexAr );
$item = implode ( '',$ret );
$item = str_pad ( $item,2,'0',STR_PAD_LEFT );
$hexColor .= $item;
}
return $hexColor;
}
?>