How to replace all occurences of a variable in a string using javascript?

Question

I'm trying to replace all the occurrences of a variable in a string using javascript.

This is not working.:

var id = "__1";
var re = new RegExp('/' + id + '/g');
var newHtml = oldHtml.replace( re, "__2");

This is only replacing the first occurrence of id:

var id = "__1";
var newHtml = oldHtml.replace( id,"__2");

What am I doing wrong here?

Thanks

VoteyDisciple · Accepted Answer · 2009-08-17 17:36:16Z

12

When you instantiate the RegExp object, you don't need to use slashes; the flags are passed as a second argument. For example:

var id = "__1";
var re = new RegExp(id, 'g');
var newHtml = oldHtml.replace( re, "__2");

answered Aug 17, 2009 at 17:36

VoteyDisciple

37.9k5 gold badges100 silver badges100 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

This won't work if there are regex characters in id

mcandre · Accepted Answer · 2009-08-17 17:39:27Z

0

You need the slashes before and after the string to replace (id).

answered Aug 17, 2009 at 17:39

mcandre

25k21 gold badges93 silver badges150 bronze badges