JS color translate css from RGB to HEX

rgb.to.hex.js

//usage
//alert (RGB_to_HEX('rgb(119,110,200)'));

function RGB_to_HEX(RGB)
    {
      var parts = RGB
        .match(/^rgb\((\d+),\s*(\d+),\s*(\d+)\)$/);
        // parts now should be ["rgb(0, 70, 255", "0", "70", "255"]
        delete (parts[0]);
        for (var i = 1; i <= 3; ++i) {
            parts[i] = parseInt(parts[i]).toString(16);
            if (parts[i].length == 1) parts[i] = '0' + parts[i];
            }
        return '#' + parts.join(''); // "0070ff"
        //thanks to http://stackoverflow.com/questions/638948/background-color-hex-to-javascript-variable-jquery
    }