How to check whether a string contains a substring in JavaScript?

Problem

Usually I would expect a String.contains() method but there doesn't seem to be one. What is a reasonable way to check for this in javascript ?

Answer

Here is a list of current possibilities:

• indexOf

  var string = "foo",
substring = "oo";
string.indexOf(substring) !== -1;

• includes

  var string = "foo",
substring = "oo";
string.includes(substring);

• search

  var string = "foo",
expr = /oo/; // no quotes here
expr.test(string);

• RegExp

  var string = "foo",
expr = /oo/;
string.match(expr);

• Match

  var string = "foo",
expr = /oo/;
string.search(expr);