JavaScript: Create an object from the given key-value pairs

JavaScript fundamental (ES6 Syntax): Exercise-41 with Solution

Object from Key-Value Pairs

Write a JavaScript program to create an object from the given key-value pairs.

• Use Array.prototype.reduce() to create and combine key-value pairs.

Sample Solution:

JavaScript Code:

//#Source https://bit.ly/2neWfJ2
// Define a function 'object_From_Pairs' that takes an array 'arr' of key-value pairs as input.
const object_From_Pairs = arr =>
  // Reduce the array to an object by iteratively assigning key-value pairs.
  arr.reduce((a, v) => ((a[v[0]] = v[1]), a), {});

// Test the 'object_From_Pairs' function with different arrays of key-value pairs and output the resulting objects.
console.log(object_From_Pairs([['a', 1], ['b', 2]])); // Output: { a: 1, b: 2 }
console.log(object_From_Pairs([[1, 10], [2, 20], [3, 30]])); // Output: { '1': 10, '2': 20, '3': 30 }

Output:

{"a":1,"b":2}
{"1":10,"2":20,"3":30}

Visual Presentation:

Flowchart:

Live Demo:

See the Pen javascript-basic-exercise-1-41 by w3resource (@w3resource) on CodePen.

For more Practice: Solve these Related Problems:

• Write a JavaScript program that creates an object from an array of key-value pair arrays.
• Write a JavaScript function that reconstructs an object using the reduce() method on an array of key-value pairs.
• Write a JavaScript program that merges an array of [key, value] pairs into an object, handling duplicate keys by overwriting.

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