Javascript Object.defineProperties()

The syntax of the defineProperties() method is:

Object.defineProperties(obj, props)

The defineProperties() method, being a static method, is called using the Object class name.

defineProperties() Parameters

The defineProperties() method takes in:

1. obj - The object on which to define or modify properties.
2. props - An object whose keys represent the names of properties to be defined or modified and whose values are objects describing those properties.
   Each props value must either be a data descriptor or accessor descriptor. They can have the following optional properties.
   1. configurable
   2. enumerable
   Data descriptors can also have:
   1. value
   2. writable
   Accessor descriptors can also have:
   1. get
   2. set

Return value from defineProperties()

• Returns the object that was passed to the function.

Note: If a descriptor has neither of value, writable, get and set keys, it is treated as a data descriptor. If a descriptor has both value or writable and get or set keys, an exception is thrown.

Example: Using Object.defineProperties()

let obj = {};
Object.defineProperties(obj, {
  property1: {
    value: true,
    writable: true,
  },
  property2: {
    value: "Hello",
    writable: false,
  },
});

console.log(obj); // {property1: true, property2: "Hello"}

Output

{property1: true, property2: "Hello"}

Recommended Reading: Javascript Object defineProperty()