Why string replace in JS doesn't replace all characters

Question

"-x-x+x".replace('-', '+')

equals

"+x-x+x"

why isn't the second - replaced?

.replace only replace the first instance(character). to replace all instances you have to use regex.. console.log('-x-x+x'.replace(/-/g, '+')); — wakakak, Jan 22 '20 at 22:01
Searching StackOverflow for "[javascript] replace all instances" pulls up many duplicate posts asking essentially the same question. — Taplar, Jan 22 '20 at 22:08

score 2 · Accepted Answer · answered Jan 22 '20 at 22:02

2

.replace only replaces the first instance it finds. To replace all of them, use a regex:

"-x-x+x".replace(/-/g, '+')

Note the /g at the end of the regex: it indicates "global" mode. Without it you'll still only replace the first instance.

answered Jan 22 '20 at 22:02

Alastair

Thanks for this, I was trying to find what the `/g` meant. – Jack Averill Nov 30 '22 at 13:22

score 1 · Answer 2 · answered Jan 22 '20 at 22:02

1

Convert it to regex to replace all.

console.log("-x-x+x".replace(/-/g, '+'))

answered Jan 22 '20 at 22:02

Addis

customcommander · Answer 3 · 2020-01-23T00:11:44.130

1

This is explained in the documentation for String#replace:

Use a regular expression:

'-x-x+x'.replace(/-/g, '+')
//=> "+x+x+x"

edited Jan 23 '20 at 00:11

answered Jan 22 '20 at 22:07

customcommander

3 Answers3