var rgb = '220,20,60';

alert(rgb2hex(rgb));

//将RGB转换成#HEX

function rgb2hex(rgb) {

    var reg=/(\d{1,3}),(\d{1,3}),(\d{1,3})/;

    var arr=reg.exec(rgb);

    function hex(x) {

        return ("0" + parseInt(x).toString(16)).slice(-2);

    }

    var _hex="#" + hex(arr[1]) + hex(arr[2]) + hex(arr[3]);

    return _hex.toUpperCase();

}