Comments on: Javascript regular expressions

By: Gareth Heyes

Gareth Heyes — Tue, 29 Dec 2009 09:23:48 +0000

var str = “hello [bob] hello hello [bob]!”;
str=str.replace(/\[bob\]/g,’”bob”‘);

Manish — Tue, 29 Dec 2009 05:08:09 +0000

if
var str = “hello [bob] hello hello [bob]!”;
then how to replace “[bob]” with “bob” only through javascript.
Can anyone sovle it?

Gareth Heyes — Mon, 23 Feb 2009 10:29:38 +0000

@mar

I think this is what you mean:-

var str = "hello bob hello hello bob!";
var s = "bob";
alert( str.replace(new RegExp(s,'g'), function(str) { return 'yes';}));

You need to use the RegExp constructor to dynamically create regular expressions.

Mar canet — Sun, 22 Feb 2009 22:14:46 +0000

I don’t know how to add a variable string this remplace and regular expresion function.

var str = “hello bob hello hello bob!”;
var s = “bob”;
alert( str.replace(/s/+/g, function(str) { return str.replace(/s/g,’yes’);}) );

could you show how to do it?

Ronald — Sat, 02 Feb 2008 13:54:49 +0000

Good stuff Gareth!

@.mario: yeah exactly that was the stuff I needed to wrap my head around.

riahmatic — Sat, 02 Feb 2008 01:35:03 +0000

you can also eval a string formated like a regex to pass variables:

var a = ‘/[test]+/’;
alert(eval(a+’i').exec(’TeSt’));

.mario — Fri, 01 Feb 2008 23:00:44 +0000

Nice article! I especially “like” the fact that JS allows match sniffing - try to use console.dir(RegExp) with noscript installed