Add Alpha Channel to Background Color using jQuery / JavaScript -

i have jquery function adds alpha channel background-color when event occur.

here jsfiddle.

css

div { background-color: rgb(100,100,100); } 

javascript

function addalphachannel() {     var oldbgcolor = $('div').css('backgroundcolor'); //rgb(100,100,100)     var newbgcolor = oldbgcolor.replace('rgb', 'rgba').replace(')', ',.8)'); //rgba(100,100,100,.8)      $('div').css({ backgroundcolor: newbgcolor }); } 

this code works fine, wonder if there better way of adding/changing alpha channel?

any appreciated.

if want change rgba css property using javascript, you'll need use replace method, however, can improve code this:

css

 div { background-color: rgba(100, 100, 100, 1.0); } 

js

function addalphachannel() {     var oldbgcolor = $('div').css('background-color'), //rgb(100,100,100),         newbgcolor = oldbgcolor.replace(/[^,]+(?=\))/, '0.8'); //rgba(100,100,100,.8);      $('div').css({ backgroundcolor: newbgcolor }); } 

hope can you.