When Should You Choose Map Over Object in JavaScript?

Map vs Object in JavaScript

While JavaScript objects act as dictionaries, the Map object provides a more specialized key-value mapping solution with distinct features that set it apart.

Key Differences Between Map and Object

1. Order of Elements: Maps preserve the order of key-value pairs based on insertion, which can be iterated over in the same order.
2. Key Type: Unlike objects where keys are only strings, Maps allow keys of any value type, including undefined and symbols.
3. Prototype Absence: Maps do not have a prototype, eliminating default keys present in objects. This can be useful to avoid potential conflicts.
4. Size Tracking: Maps include a size property to accurately track the number of key-value pairs, unlike objects where size needs to be manually counted.
5. Iteration Speed: Maps leverage sublinear access times for iteration, regardless of the number of elements stored.

Advantages of Using Map

• Ensures consistent iteration order across browsers.
• Enables quick check for value presence using myMap.has(key).
• Provides convenient tracking of map size through myMap.size.
• Eliminates potential naming conflicts with prototype-based key lookups.

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