How To Check If A Variable Is A Typed Array In Javascript

So, you're working on a JavaScript project and you need to figure out if a variable is a typed array. No worries, I've got you covered! In this article, I'm going to break down how you can easily check if a variable is a typed array in JavaScript. Let's dive in!

In JavaScript, a typed array is a structured array of a specific data type – like Int8Array, Uint8Array, Float32Array, and so on. To determine if a variable is a typed array, you can use the 'ArrayBuffer.isView()' method. This method checks if an object is a typed array view.

Here’s a simple example to illustrate how you can use this method:

const arr1 = new Float32Array();
const arr2 = [1, 2, 3];

console.log(ArrayBuffer.isView(arr1)); // true
console.log(ArrayBuffer.isView(arr2)); // false

In the above code snippet, we create two variables, 'arr1' as a Float32Array typed array and 'arr2' as a regular array. We then use the 'ArrayBuffer.isView()' method to check if each variable is a typed array. The method returns 'true' for 'arr1' and 'false' for 'arr2'.

Another way to check for a typed array is by using the 'instanceof' operator. The 'instanceof' operator tests whether an object has the prototype property of a constructor.

const arr = new Int8Array();

console.log(arr instanceof Int8Array); // true
console.log(arr instanceof Uint8Array); // false

In this snippet, 'arr' is an Int8Array typed array. Using the 'instanceof' operator, we check if 'arr' is an instance of Int8Array, which returns 'true', and if it's an instance of Uint8Array, which returns 'false'.

Additionally, if you want a more specific check for each type of typed array, you can use the 'constructor' property of the variable.

const arr = new Int32Array();

if (arr.constructor === Int32Array) {
  console.log('Variable is an Int32Array!');
} else {
  console.log('Variable is not an Int32Array!');
}

In the code above, we create a variable 'arr' as an Int32Array typed array. By accessing the 'constructor' property of 'arr', we can specifically check if the variable is an Int32Array.

So, the next time you need to determine if a variable is a typed array in JavaScript, remember to leverage the 'ArrayBuffer.isView()' method, the 'instanceof' operator, or the 'constructor' property based on your specific needs. Happy coding!