JavaScript RegExp including flags in pattern

Question

var str = 'TEST, STRING';
var regex = new RegExp('^(.*)('+str+')(.*)$/i');
console.log(regex);

Output

/^(.*)(TEST, STRING)(.*)$\/i/

But I need the following output:

/^(.*)(TEST, STRING)(.*)$\/i

If your problem is solved, please accept the answer. See How does accepting an answer work? — Tushar
– Tushar, Commented Mar 4, 2016 at 13:20

Tushar · Accepted Answer · 2016-02-29 04:28:53Z

4

The flags should be the second parameter to the RegExp constructor.

new RegExp('^(.*)(' + str + ')(.*)$', 'i');
                                    ^ ^^^

The syntax of RegExp constructor is

new RegExp(pattern[, flags])

answered Feb 29, 2016 at 4:26

Tushar

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4 Comments

Use ` RegExp('^(.*)('+str+')(.*)$\//i'); `

@ArifBurhan And that'll give /^(.*)(TEST, STRING)(.*)$\/\/i/

Only ` \\ ` can output ` \ `

@ArifBurhan You're not getting it. The first param to the RegExp constructor is the pattern. To add flags, use second param.