Regex test with parentheses

Question

I have code like this:

  var value = "Mary Jane (Asistant)";
  var regex = new RegExp(value);
  regex.test("Some String to Test");

I want to test my regex.It works when I have closed parentheses.But when I test for example value of "Mary Jane (Asistant" it throws error.

Invalid regular expression: /Mary Jane (Asistant/: Unterminated group.

How can I get rid of this error?

You yourself mention the solution: close the group. Unless you want to match literal parentheses. Then you must escape the literal string to be used as part of a regex pattern. — Wiktor Stribiżew, Feb 05 '19 at 13:04
I suggest you test your regex on a live preview site like regex101.com where you get detailed error messages https://regex101.com/r/4YoBIe/1 — goosmaster, Feb 05 '19 at 13:05

Kamil Kiełczewski · Answer 1 · 2019-02-05T13:24:14.033

Try this

var value = "Mary Jane \\(Asistant\\)";
var regex = new RegExp(value);

console.log(regex.test("Some String to Test"));
console.log(regex.test("Mary Jane (Asistant)"));

or this

var value = /Mary Jane \(Asistant\)/;
var regex = new RegExp(value);

console.log(regex.test("Some String to Test"));
console.log(regex.test("Mary Jane (Asistant)"));

remember that value contains regular expression pattern and some characters like parenthesis ( and ) has special meaning and need to be escaped like in snippets above.

Regex test with parentheses

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