JavaScript: Convert an object into a list of pairs

JavaScript Object: Exercise-15 with Solution

Object to Key-Value Pairs

Write a JavaScript function to convert an object into a list of '[key, value]' pairs.

Sample Solution:

JavaScript Code:

function key_value_pairs(obj) 
   {
    var keys = _keys(obj);
    var length = keys.length;
    var pairs = Array(length);
    for (var i = 0; i < length; i++) 
    {
      pairs[i] = [keys[i], obj[keys[i]]];
    }
    return pairs;
  }

function _keys(obj) 
  {
    if (!isObject(obj)) return [];
    if (Object.keys) return Object.keys(obj);
    var keys = [];
    for (var key in obj) if (_.has(obj, key)) keys.push(key);
    return keys;
  }
function isObject(obj) 
 {
    var type = typeof obj;
    return type === 'function' || type === 'object' && !!obj;
  }
console.log(key_value_pairs({red: "#FF0000", green: "#00FF00", white: "#FFFFFF"}));

Output:

[["red","#FF0000"],["green","#00FF00"],["white","#FFFFFF"]]

Flowchart:

Live Demo:

See the Pen javascript-object-exercise-15 by w3resource (@w3resource) on CodePen.

For more Practice: Solve these Related Problems:

• Write a JavaScript function that converts an object into an array of [key, value] pairs using Object.entries().
• Write a JavaScript function that manually iterates over an object’s properties to form an array of key-value pairs.
• Write a JavaScript function that sorts the key-value pairs alphabetically by key before returning them.
• Write a JavaScript function that flattens nested objects into a list of key-value pairs using dot notation for keys.

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