Javascript - Regex : How to replace id in string with the same id plus number? -

i have string multiple elements id's below:

var data = "<div id='1'></div><input type='text' id='2'/>"; 

now i'm using regex find id's in string:

var reg = /id="([^"]+)"/g; 

afterwards want replace id's new id. this:

data = data.replace(reg, + 'id="' + reg2 + '_' + numcompare + '"'); 

i want reg2, seen above, return value of id's. i'm not familiar regular expressions, how can go doing this?

instead of using regex, parse , loop through elements. try:

var data = "<div id='1'></div><div id='asdf'><input type='text' id='2'/></div>",     numcompare = 23,     div = document.createelement("div"),     i, cur;  div.innerhtml = data;  function updateid(parent) {     var children = parent.children;     (i = 0; < children.length; i++) {         cur = children[i];         if (cur.nodetype === 1 && cur.id) {             cur.id = cur.id + "_" + numcompare;         }         updateid(cur);     } }  updateid(div); 

demo: http://jsfiddle.net/rbuag/3/

this checks see if id set in first place, , modify it.

also, safe in case html contains comment node (where ie 6-8 include comment nodes in .children).

also, walks through children of elements. in example, had 1 level of elements (no nested). in fiddle, nest <input /> , still modified.

to get updated html, use div.innerhtml.

with jquery, can try:

var data = "<div id='1'></div><div id='asdf'><input type='text' id='2'/></div>",     numcompare = 23,     div = $("<div>"),     i, cur;  div.append(data);  div.find("[id]").each(function () {     $(this).attr("id", function (index, attr) {         return attr + "_" + numcompare;     }); }); 

demo: http://jsfiddle.net/txfwh/5/

while it's valid have id start and/or number, should change id of elements normal identifier.

references:

• .children: https://developer.mozilla.org/en-us/docs/dom/element.children
• .nodetype: https://developer.mozilla.org/en-us/docs/dom/node.nodetype
• jquery.find(): http://api.jquery.com/find/
• jquery.attr(): http://api.jquery.com/attr/
• jquery.each(): http://api.jquery.com/each/