In JavaScript, a map is a component of a keyed collection. This indicates that this data structure stores information in the form of keys and values.

An object is made up of a number of properties, each of which has a key and a corresponding value.

Does this imply that the object and the map are comparable to one another?
Both enable us to assign values to keys, retrieve those values, delete keys, and determine whether a key has been used to store a particular object. Objects were formerly used as maps because of this. However, there are significant distinctions that, in some circumstances, make utilizing a map preferable.

  • Depending on the kind of key:

JavaScript Map enables you to have a key-value pair in which the key could be an object, a function, or even a primitive type.

Conversely, Object lets you create a key-value pair where the key can only be of type String. Therefore, a key of type integer will be transformed to a string even if it is assigned.

  • Considering how we can refine them:

Because Map is a built-in iterable in JavaScript, you can use the forEach loop to loop through each element in the Map.

On the other hand, Object is not iterable. We must obtain either entries, keys, or values that are returned as arrays and then iterate over them if we want to loop through every field in the object.

  • Based on how we calculate size:

By using the size attribute, you may quickly determine a Map's size. The total number of entries in the Map is returned by this.

The size of an Object cannot be determined directly by any method or property. An Object's property count must be manually calculated.

  • Depending on how you make a JSON string out of them:

Since Map is a pure hash table, JSON is not directly supported. To convert Map into a JSON string, you must supply your own parser.

With Objects, you receive direct support for using JSON.stringify to turn them into JSON strings ().

  • Other possibilities

Keys added to an object are not ordered, whereas keys in a map are. A Map object therefore returns keys in order of insertion when iterating over it.
In situations where key pairs are frequently added and removed, a Map might perform better.


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