Returns a boolean indicating whether an array includes an item. Generally, you can use the includes() and some() methods, which will return boolean values, or indexOf() and findIndex(), which will return the index of the first occurence of the value found. ![]() There’s more than one way to check if an array contains a value in JavaScript. So let’s not waste any time and help you find out. Since you’re here, I take it you want to learn to check if an array-type object contains a given value. I hope you find this article useful.The more you learn about JavaScript, the more you realize you need to learn. If you work with TypeScript, you could incorporate to your application also the snippet that checks for empty array.ĭepending on your needs, you can choose one or more approaches and combine them together, or you could also write helper functions like the one for Typescript. ?, Nullish coalescing operator ? and finally isArray() method. We started with the length property and introduced operators like &, optional chaining. I listed several ways we can utilize the operators to work with the arrays and check whether they are empty or not. While the object uses curly brackets: let myObject = Conclusion The literal syntax of the array uses square brackets: let myArray = That means it extends the behaviour of JS object in some way. JS arrays serve for storing the multiple values in a list. ![]() If you work with Typescript (TS), there’s an interesting and more bullet proof way to check for empty arrays too. ![]() There are more ways to do it so I’ll describe them gradually since JS language is evolving and now we have better and more concise ways to do it. I’ll shortly describe what Javascript (JS) array is, how we use it and then I’ll describe how we can check whether it’s empty.
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