Yes, the str string contains the string substring.Įxample-4: Using various capitalization cases Ĭonsole.log(str.includes('string', -3)) // true Here is an example using a negative index. Specifying a starting index less than the substring's leads to searching the substring throughout the entire string. But does it start at index 13?Įxample-3: Using a substring and a negative starting position It is true that the string substring starts at index 11 in the str string. Ĭonsole.log(str.includes('string', 11)) // true We can also check whether the target substring is located at a specific index. It is true that the string JavaScript string contains is easy contains the string substring.Įxample-2: Using a substring and a starting position The code example below shows how you can use the indexOf method to check if a string contains a substring in ECMAScript 5 or older.Now let's dive into practical examples of the includes() method.Ĭonst str = document.querySelector('p').textContentĬonsole.log(str.includes('string')) // true } Option 2: Use the indexOf Method (ECMAScript 5 or older) run this code if People is present in the str constant const str = 'We the People of the United States, in Order to form a more perfect Union.' Ĭonsole.log(str.includes('We the')) // trueĬonsole.log(str.includes('Order')) // trueĬonsole.log(str.includes('notpresent')) // falseĬonsole.log(str.includes('WE THE')) // false The code snippet below shows you how to use the includes method to check if a string contains a substring in ECMAScript 6. Option 1: Use the includes Method (ECMAScript 6) One of the ways is done using the includes method for JavaScript 6 (ECMAScript 6) and the other is with the indexOf for JavaScript 5 (ECMAScript 5) or older. There are two simple ways to check if a string contains a substring in JavaScript.

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