Javascript string manipulation with regular expressions

Question

I have a string like this

"#G=0&path=folder1"

I want to find a part after "path=" which is folder1 in this case, and replace it with something else, so the string will look like this:

"#G=0&path=file2"

How can I do this using Javascript regular expressions?

Are you using a document fragment as a query-string? Parsing query strings correctly is a bit more work than one simple regex. — zzzzBov
– zzzzBov, Commented Jan 18, 2013 at 19:50

VisioN · Accepted Answer · 2013-01-18 19:48:29Z

1

One possible regex solution:

"#G=0&path=folder1".replace(/(&?path=).*$/, "$1" + "file2");

Or you can do it without regex:

str.substring(0, str.lastIndexOf("=") + 1) + "file2";

answered Jan 18, 2013 at 19:48

VisioN

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Comments

MikeM · Accepted Answer · 2013-01-18 23:49:52Z

0

See, for example, Regular-Expressions.info, MDN replace and here, and educate yourself about regular expressions, they are very useful.

var str = '#G=0&path=folder1';
var file = 'file2';

str = str.replace( /^(#G=0&path=).+$/, '$1' + file );

console.log( str );    // #G=0&path=file2

answered Jan 18, 2013 at 23:49

MikeM

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