如何删除数组中每个对象的属性？

Question

Let say I have

let a = [{
  foo: 1
  bar: 1
  baz: 1
},{
  foo: 2
  bar: 2
  baz: 2
},{
  foo: 3
  bar: 3,
  baz: 3
}];

How can I remove bar in every object so I get

a = [{ foo: 1, baz: 1 }, { foo: 2, baz: 2 }, { foo: 3, baz: 3 }];

I simplified the example but each object can have many properties.

Answer 1

Use .map to transform each element of an array into another. Also note that your snippet's syntax is invalid; properties of an object need to be separated with a comma.

 const input = [{ foo: 1, bar: 1 },{ foo: 2, bar: 2 },{ foo: 3, bar: 3 }]; const output = input.map(({ foo }) => ({ foo })); console.log(output); 

If you want to remove one property rather than save some particular properties, you can do something similar using object rest/spread:

 const input = [{ foo: 1, bar: 1, baz: 1 },{ foo: 2, bar: 2, baz: 2 },{ foo: 3, bar: 3, baz: 3 }]; const output = input.map(({ foo, ...otherProps }) => ({ ...otherProps })); console.log(output); 

Answer 2

use Object.assign so you don't loose the first object and create a new one with the desired properties :

 const a = [{ foo: 1, bar: 1, baz: 1 },{ foo: 2, bar: 2, baz: 2 },{ foo: 3, bar: 3, baz: 3 }]; const b = Object.assign(a.map(({foo, baz}) => ({foo, baz}) ), {}); console.log( JSON.stringify(b) ) console.log(a)