TypeScript Object values()

In this chapter, we will explore the Object.values() method in TypeScript. This method returns an array of a given object's own enumerable property values. Understanding how to use Object.values() is useful for iterating over an object's values.

Table of Contents

1. Definition
2. Syntax
3. Examples
4. Conclusion

1. Definition

The Object.values() method returns an array of a given object's own enumerable property values. This is useful for iterating over an object's values.

2. Syntax

Object.values(obj);

Parameters

• obj: The object whose own enumerable property values are to be returned.

Return Value

The method returns an array of the given object's own enumerable property values.

3. Examples

Let's look at some examples to understand how Object.values() works in TypeScript.

Example 1: Basic Usage

This example shows how to use Object.values() to get an array of values from an object.

let person = {
  name: "Ravi",
  age: 25,
  city: "Mumbai"
};

let values = Object.values(person);
console.log(values);
// Output: [ 'Ravi', 25, 'Mumbai' ]

Example 2: Iterating Over Values

This example shows how to iterate over the values returned by Object.values().

let person = {
  name: "Ravi",
  age: 25,
  city: "Mumbai"
};

for (let value of Object.values(person)) {
  console.log(value);
}
// Output:
// Ravi
// 25
// Mumbai

Example 3: Using Object.values() with Arrays

This example shows how Object.values() can be used with arrays.

let fruits = ["apple", "banana", "mango"];
let values = Object.values(fruits);
console.log(values);
// Output: [ 'apple', 'banana', 'mango' ]

Example 4: Filtering Values

This example shows how to filter the values of an object using Object.values().

let person = {
  name: "Ravi",
  age: 25,
  city: "Mumbai"
};

let filteredValues = Object.values(person).filter(value => typeof value === 'number');
console.log(filteredValues);
// Output: [ 25 ]

Example 5: Handling Non-Enumerable Properties

This example shows how Object.values() handles non-enumerable properties.

let person = {
  name: "Ravi",
  age: 25
};

Object.defineProperty(person, 'city', {
  value: "Mumbai",
  enumerable: false
});

let values = Object.values(person);
console.log(values);
// Output: [ 'Ravi', 25 ]

Example 6: Using Object.values() with Nested Objects

This example shows how to use Object.values() with nested objects.

let person = {
  name: "Ravi",
  address: {
    city: "Mumbai",
    zip: "400001"
  }
};

let values = Object.values(person);
console.log(values);
// Output: [ 'Ravi', { city: 'Mumbai', zip: '400001' } ]

let addressValues = Object.values(person.address);
console.log(addressValues);
// Output: [ 'Mumbai', '400001' ]

Example 7: Checking if an Object is Empty

This example shows how to check if an object is empty using Object.values().

let emptyObj = {};
let isEmpty = Object.values(emptyObj).length === 0;
console.log(isEmpty);
// Output: true

4. Conclusion

In this chapter, we explored the Object.values() method in TypeScript, which is used to return an array of a given object's own enumerable property values. We covered its definition, syntax, parameters, return value, and provided several examples to demonstrate its usage. Understanding how to use Object.values() is essential for iterating over an object's values in TypeScript applications.