How Do I Get a List of Keys and Their Count from a JavaScript Object?

Obtaining JavaScript Object Key Lists

In JavaScript, objects are fundamental data structures that serve as collections of key-value pairs. Retrieving these key lists is often necessary for various programming purposes. This question addresses the method for obtaining the length and list of keys stored in a JavaScript object.

Solution:

To retrieve the key list of an object, utilize the Object.keys() function built into JavaScript. The function accepts an object as its argument and returns an array containing the keys of the object as strings. Here's an example:

var obj = {
   key1: 'value1',
   key2: 'value2',
   key3: 'value3',
   key4: 'value4'
};
var keys = Object.keys(obj);
console.log('obj contains ' + keys.length + ' keys: '+  keys); // Output: obj contains 4 keys: key1,key2,key3,key4

The keys variable now contains an array of the object's keys (key1, key2, key3, key4), and the keys.length property provides the number of keys in the object (4 in this case).

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