how do you write into a getElement

Function:

var baseURL = self.location.href;

baseURL = baseURL.split("/").slice(0,3).join("/")+"/";

Code (markup):

document.getElementById(id).src = "'+baseURL+'/style/images/b.gif";

Code (markup):

The above wont write the base url '+baseURL+'

EDIT: I got it, should have been double quotes "+baseURL+"

 

document.getElementById("idName").src = baseURL+"/style/images/b.gif";