Convert a RGB colour value to Decimal

Question

How do I convert a RGB colour value to just plain decimal?

So I have: RGB(255,255,255) is white
Its decimal equivalent is: 16777215

I have tried thinking it

Answer 1

if (color.substr(0, 1) === '#') {
    return color;
}
var digits = /(.*?)rgb\((\d+), (\d+), (\d+)\)/.exec(color);
var red = parseInt(digits[2]);
var green = parseInt(digits[3]);
var blue = parseInt(digits[4]);
var rgb = blue | (green << 8) | (red << 16);
return rgb.toString(10);