How to use variable in regex

Question

I have following RegExp and it is working fine

 var reg = new RegExp(/(.{1,4})/g);

But now i want to replace 4 with variable called limit then it is not working

 var reg = new RegExp("/(.{1,"+ limit +"})/g");

How could i use variable instead of fixed value in above RegExp?

/(.{1,4})/g is RegExp literal, so you don't even need to call constructor here. — nhahtdh
– nhahtdh, Commented Jan 29, 2013 at 11:21

elclanrs · Accepted Answer · 2013-01-29 08:30:12Z

6

Drop the /. RegExp expects a string or a regex. Then it takes a second parameter where you can specify the flags.

var reg = new RegExp("(.{1,"+ limit +"})", "g");

answered Jan 29, 2013 at 8:30

elclanrs

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Comments

Cris Stringfellow · Accepted Answer · 2013-01-29 08:30:43Z

4

Like this (you don't need the /):

 var reg = new RegExp(".{1,"+ limit +"}", "g");

answered Jan 29, 2013 at 8:30

Cris Stringfellow

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Shiplu Mokaddim · Accepted Answer · 2013-01-29 08:30:13Z

3

Use it like this,

var reg = new RegExp("(.{1,"+ limit +"}", "g");

The second parameter is used for options. And the pattern does not take any delimiter.

answered Jan 29, 2013 at 8:30

Shiplu Mokaddim

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