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

Retrieving JavaScript Object Key List

Accessing and manipulating object properties is a fundamental aspect of programming in JavaScript. Extracting the list of keys from an object is often necessary for various operations such as iterating through its properties or checking for key existence.

To retrieve the key list of a JavaScript object, you can utilize the Object.keys() method. This method accepts an object as its argument and returns an array containing the property keys as strings.

Consider the following example:

var obj = {
   key1: 'value1',
   key2: 'value2',
   key3: 'value3',
   key4: 'value4'
};

var keys = Object.keys(obj);

After executing this code, the keys variable will hold an array with the property names, which are: ["key1", "key2", "key3", "key4"].

To obtain the length of the object, you can use the Object.keys().length property. In the example above, keys.length would return the value 4.

By leveraging the Object.keys() method, you can efficiently obtain the key list of a JavaScript object, enabling you to perform various operations on its properties.

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