Please show your love and support by sharing this post. Similarly, in the following cases, () does a ' strict equality comparison':Ĭonsole.log(.includes(2)) // trueĬonsole.log(.includes(4)) // falseĬonsole.log(.includes(+0)) // trueĬonsole.log(.includes(-0)) // trueĬonsole.log(.includes('foo')) // trueĬonsole.log(.includes('Foo')) // falseĬonsole.log(.includes('fo')) // false

This is the same as it would happen in a strict equals ( =) comparison: includes ( searchvalue, start) Parameters Return Value More Examples Start at position 12: let text 'Hello world, welcome to the universe.' let result text. The includes () method is case sensitive. This means, for example, that a numeric string won't equal its integer counterpart: The includes () method returns true if a string contains a specified string. Other than that one exception, Same-Value-Zero algorithm and strict equality actually yield the same result. For example:Ĭonsole.log(.includes(NaN)) // true However, in a stricter sense, the ' strict equality comparison' differs from the ( Same-Value-Zero) algorithm () method uses under the hood in terms of NaN equality. You could technically say that the JavaScript () method does a strict equality comparison of values.

Javascript includes