replace() and regex question...

[dottedquad]

I know how to use search, match, and replace... I'm just alittle confused on how I would replace a 'section' of a line when I don't know what one part of the section is....

To clear any confusion about my question... In a cookie I 'may' at one time have this:

listperpage::3;listoption::2; //field1::index#;field2::index#

The part what i won't know always is the index# because in the select field i have onchange="set_sort_cookie(name, type, value);"

        function set_sort_cookie(name, type, value){
	  var str     = document.cookie;       //set the whole cookie to a string
	  var pattern = /name./g;              //set the pattern for the RegEx to check for
	  var result  = str.search(pattern);   //RegEx the cookie to find the cookie name we're looking for

	  if (result != -1) {
            //code to replace line in cookie
          }
        }

where:

if (tresult != -1) {
//code to replace line in cookie
}

I don't know how I would replace a certain section... Could anyone give me a hand with this?

-Thanks,
Rich