php functions convert hex to rgb and rgb to hex

rgb_to_hex_to_rgb.php

function hex2rgb($hex) {
   $hex = str_replace("#", "", $hex);

   if(strlen($hex) == 3) {
      $r = hexdec(substr($hex,0,1).substr($hex,0,1));
      $g = hexdec(substr($hex,1,1).substr($hex,1,1));
      $b = hexdec(substr($hex,2,1).substr($hex,2,1));
   } else {
      $r = hexdec(substr($hex,0,2));
      $g = hexdec(substr($hex,2,2));
      $b = hexdec(substr($hex,4,2));
   }
   $rgb = array($r, $g, $b);
   //return implode(",", $rgb); // returns the rgb values separated by commas
   return $rgb; // returns an array with the rgb values
}

function rgb2hex($rgb) {
   $hex = "#";
   $hex .= str_pad(dechex($rgb[0]), 2, "0", STR_PAD_LEFT);
   $hex .= str_pad(dechex($rgb[1]), 2, "0", STR_PAD_LEFT);
   $hex .= str_pad(dechex($rgb[2]), 2, "0", STR_PAD_LEFT);

   return $hex; // returns the hex value including the number sign (#)
}

For hex2rgb you can do:

function hex2rgb($hex) { return sscanf($hex, "#%02x%02x%02x"); }