Wednesday 14 February 2018

What is Object.assign()? and how to use Object.assign()?

What is Object.assign()? and how to use Object.assign()?

Question: What is Object.assign()?
The Object.assign() is used to copy the values of all properties from one or more source objects to a target object.



Question: What is syntax for Object.assign()?
Object.assign(target, ...sources);



Example 1
const object1 = {
  a: 1,
  b: 2,
  c: 3
};
const object2 = Object.assign(object1,{d:4});
console.log(object2);

Output
Object { a: 1, b: 2, c: 3, d: 4 }



Example 2
const object1 = {
  a: 1,
  b: 2,
  c: 3
};
const object2 = Object.assign(object1,{d:4,e:5, a:11});
console.log(object2);

Output
Object { a: 11, b: 2, c: 3, d: 4, e: 5 }



Example 3
const object1 = {
  a: 1,
  b: 2,
  c: 3
};
const object2 = Object.assign(object1,{d:4,e:5, a:11},{f:5, a:111});
console.log(object2);

Output
Object { a: 111, b: 2, c: 3, d: 4, e: 5, f: 5 }



Example 4
const object1 = {
  a: 1,
  b: 2,
  c: 3
};
const object2 = Object.assign(object1,{d:4,e:5, a:11},{f:5, a:111},null, undefined);
console.log(object2);

Output
Object { a: 111, b: 2, c: 3, d: 4, e: 5, f: 5 }



Example 5
const object1 = {
  a: 1,
  b: 2,
  c: 3
};
const object2 = Object.assign(object1,{d:4,e:5, a:11},{f:5, a:111},null, undefined,{g:6, a:1111});
console.log(object2);



Output
Object { a: 1111, b: 2, c: 3, d: 4, e: 5, f: 5, g: 6 }