Approach 1: Spread Operator

One straightforward way to merge two Map objects is by using the spread operator in JavaScript. The spread operator allows us to expand elements of an iterable, such as an array or a Map, into individual elements. Here’s an example:

const map1 = new Map([['key1', 'value1'], ['key2', 'value2']]);
const map2 = new Map([['key3', 'value3'], ['key4', 'value4']]);

const mergedMap = new Map([...map1, ...map2]);

console.log(mergedMap);

In the above code, we create two Map objects map1 and map2. We then use the spread operator ... to merge them into a new Map object mergedMap. Finally, we log the result to the console.

Approach 2: Iterating and inserting

Another approach is to iterate over one Map object and insert its key-value pairs into another Map object. This can be achieved using the Map.prototype.set() method. Here’s an example:

const map1 = new Map([['key1', 'value1'], ['key2', 'value2']]);
const map2 = new Map([['key3', 'value3'], ['key4', 'value4']]);

const mergedMap = new Map(map1);

for (const [key, value] of map2) {
  mergedMap.set(key, value);
}

console.log(mergedMap);

In the above code, we initialize mergedMap with the contents of map1 using new Map(map1). Then, using a for...of loop, we iterate over map2 and insert each key-value pair into mergedMap using the set() method.

Conclusion

Merging two Map objects can be done efficiently using either the spread operator or by iterating and inserting the key-value pairs. Both approaches offer flexibility and can help you manipulate and combine Maps in your JavaScript applications. So choose the approach that best suits your specific use case and start merging those Maps!

#JavaScript #Map #Merge