Dive Into TypeScript Maps

Today, we're diving into maps in TypeScript. A map in TypeScript stores data as key-value pairs, emphasizing type safety by allowing you to define specific types for keys and values. We'll explore how to create maps with type annotations and delve into the intricacies of their performance.

Maps in TypeScript are versatile data structures. They store key-value pairs and allow you to set defined types for each, ensuring type safety throughout your codebase.

Here is how we create an empty map with specific types for keys and values:

let myMap: Map<string, number> = new Map(); // creates an empty Map with string keys and number values

In the code above, myMap is a new TypeScript map, specifically defined to accept string keys and number values, ensuring robust and error-free storage.

Maps in TypeScript come equipped with essential methods:

• set(key, value): Stores a key-value pair.
• get(key): Retrieves the value associated with a key.
• has(key): Checks if a key exists and returns true or false.
• delete(key): Removes a key-value pair.
• size: Returns the count of key-value pairs.

To better understand these methods, let's apply them:

let myMap: Map<string, number> = new Map();

// Add pairs with set
myMap.set('apples', 10); // Adds a new pair
myMap.set('bananas', 6); // Adds another pair

// Use get
console.log(myMap.get('apples')); // Outputs: 10, retrieves the value for 'apples'

// Apply has
console.log(myMap.has('bananas')); // Outputs: true, checks for the existence of 'bananas'

// Delete with delete
myMap.delete('bananas'); // Removes 'bananas' and its value from the map

// Check size
console.log(myMap.size); // Outputs: 1, gives the number of pairs