Basics
JS Maps
Working with JavaScript Maps
JavaScript Maps store key-value pairs, with methods like set and get.
Introduction to JavaScript Maps
JavaScript Maps are a powerful feature that allow developers to store collections of key-value pairs. Unlike JavaScript objects, Maps can use any data type as a key, offering greater flexibility and performance advantages. This makes them an essential tool for managing collections of data.
Creating a Map
To create a new Map, use the Map constructor. You can initialize a Map without any arguments or pass an iterable, such as an array, to set initial key-value pairs.
Adding and Retrieving Values
To add key-value pairs to a Map, use the set method. To retrieve a value, use the get method by providing the key.
Checking for Keys and Deleting Entries
Maps provide the has method to check if a key exists, and the delete method to remove key-value pairs.
Iterating Over a Map
You can iterate over a Map using the forEach method, or by using a for...of loop with the entries, keys, or values methods.
Map Size and Clearing Maps
Use the size property to get the number of key-value pairs in a Map. The clear method removes all entries from a Map.
Basics
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