If we modify our str to 'I LOVE freeCodeCamp' and the search-string is still 'love', then the return value would be false. Since the word 'love' is included inside the str, then the code will return true. In the code, str would be 'I love freeCodeCamp' and the search-string would be 'love'. We want to see if the word 'love' is included in that sentence. In this first example, we have the sentence, 'I love freeCodeCamp'. If the search-string is not found then it will return false. If the search-string is found then it will return true. If the position parameter is omitted then the default is zero. The position parameter is an optional number for the starting search position in the str. The search-string parameter is the string you are searching for in str. includes() method: str.includes(search-string, optional-position) In this article, I will walk you through a few code examples of the JavaScript string method called. includes() method to see if one string is found in another. So you may want to rewrite your code as follows: function contains(a, obj) )) //falseĬonsole.log(.In JavaScript you can use the. If you need the best performance, benchmark for yourself in the relevant execution environments.Īs others have said, the iteration through the array is probably the best way, but it has been proven that a decreasing while loop is the fastest way to iterate in JavaScript.

If you need an easy solution, look for other answers.

It might not be relevant to modern JS execution contexts. The promised performance improvement was based on a benchmark done in browsers of that time. Update from 2019: This answer is from 2008 (11 years old!) and is not relevant for modern JS usage.

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