How to declare a variable in TypeScript

How to declare a variable in TypeScript

Source:- How to declare a variable in TypeScript

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In TypeScript, you can declare a variable using the `let` or `const` keyword, just like in JavaScript. However, TypeScript also allows you to specify the variable type using type annotations.

Here are a few examples:

// Declaring a variable with a type annotation
let myNumber: number = 42;

// Declaring a variable without a type annotation
let myString = "Hello, world!";

// Declaring a constant with a type annotation
const PI: number = 3.14;

// Declaring a variable with an array type
let myArray: string[] = ["apple", "banana", "orange"];

// Declaring a variable with an object type
let myObject: { name: string, age: number } = { name: "Alice", age: 30 };

In the first example, we declare a variable `myNumber` of type `number` and assign it the value `42`. In the second example, we declare a variable `myString` and TypeScript infers its type to be `string` based on the value `”Hello, world!”`.

In the third example, we declare a constant `PI` of type `number` and assign it the value `3.14`.

In the fourth example, we declare a variable `myArray` of type `string[]`, which is an array of strings. We…