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The TypeScript forEach method calls a function once for every element of an array: orders.forEach((order, index) => { … }). TypeScript infers the element type for the callback, and forEach always returns void, so use it for side effects such as logging or totals: My setup for these examples: TypeScript 7.0.2 and Node.js v22.22.2, compiled … Read more >>
To get distinct values from an array in TypeScript, pass the array to a Set and spread it back: […new Set(arr)]. A Set keeps each value once, in first-seen order, and TypeScript keeps the element type, so a string[] stays a string[]: I compiled these snippets with TypeScript 7.0.2 running on Node.js v22.22.2. One of … Read more >>
In this tutorial, I will explain how to use the const arrays in TypeScript. I will also show you some examples of using const arrays in TypeScript. What is a Const Array in TypeScript? Let me first explain what a const array is in TypeScript. The const keyword in TypeScript is used to declare variables … Read more >>
The TypeScript array splice() method changes an array in place: arr.splice(start, deleteCount, …items) removes deleteCount elements at start, inserts any items there, and returns the removed elements as a new array. Use toSpliced() when you need a copy instead: My test bench was TypeScript 7.0.2 with Node v22.22.2, strict mode on, and the printed arrays … Read more >>
The quickest TypeScript enum to array conversion is a single call: pass the enum to Object.values() for its values or Object.keys() for its names. A string enum gives you a clean array right away; a numeric enum needs one filter() first: My setup for this page was TypeScript 7.0.2 and Node.js v22.22.2 with strict mode … Read more >>
To convert an object to an array in TypeScript, use Object.values(obj) for the values, Object.keys(obj) for the property names, or Object.entries(obj) for [key, value] pairs. Each returns a new array and leaves the object alone: These examples were compiled with –strict and run with TypeScript 7.0.2 on Node.js v22.22.2; nothing below is hand-typed output. You’ll … Read more >>
If you are a TypeScript developer working with arrays, this tutorial will be very helpful. In it, I explained how to convert an array to a string in TypeScript. Let’s understand why you might need to convert an array to a string. Arrays are versatile data structures that can hold multiple values, but sometimes you … Read more >>
To convert a string to an array in TypeScript, use split() with a separator, such as “a,b,c”.split(“,”), which returns a string[]. For an array of single characters, use Array.from(str) instead of split(“”): Here I’m compiling in strict mode with TypeScript 7.0.2 with Node.js v22.22.2, and each output block is pasted from the console. You’ll see … Read more >>
Spread syntax is the quickest way to convert a Set to an array in TypeScript: […mySet]. Array.from(mySet) does the same job. Both return a new, typed array in insertion order, so a Set<string> becomes a string[]: I compiled and ran every example below with TypeScript 7.0.2 and Node.js v22.22.2 in strict mode, and the outputs … Read more >>
In this tutorial, I will explain how to use TypeScript’s join() method to combine an array of strings into a single string. This method is particularly useful when you need to create a comma-separated list, format strings for display, or generate URLs from an array of parameters. What Is The Join() Method in TypeScript The … Read more >>