将 Javascript 嵌套 Object 逐一更新

Question

I have this kind of object:

  {
   a:{name:'a'},
   b:{name:'b'},
   c:{name:'c'},
}

And my goal is to add new key/value pair to each object. So final result shall look like this:

 {
   a:{name:'a',newField:false},
   b:{name:'b',newField:false},
   c:{name:'c',newField:false},
}

So far I've tried to put my current object into array and loop through but I had no success at all since I am getting only first level of key/value pairs.

Any suggestions please?

Answer 1

The easiest way to accomplish this it to use a for...in loop.

 const data = { a: { name: 'a' }, b: { name: 'b' }, c: { name: 'c' }, }; for (let key in data) { data[key].newField = false; } console.log(data);

 .as-console-wrapper { top: 0; max-height: 100%;important; }

If you do not wish to mutate the data you can try the following:

 const data = { a: { name: 'a' }, b: { name: 'b' }, c: { name: 'c' }, }; const copy = Object.fromEntries(Object.entries(data).map(([key, val]) => [key, {...val, newField: false }])); console.log(copy);

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Answer 2

If you're happy mutating the object rather than creating a new one use a for...in loop .

 const obj = { a: {name:'a'}, b: {name:'b'}, c: {name:'c'}, }; for (let key in obj) { obj[key].newField = false; } console.log(obj);

Answer 3

a for..in should do it

for (const key in yourObject) {
  yourObject[key].newField = false
}

Answer 4

try this:

const orig_obj = {
   a:{name:'a'},
   b:{name:'b'},
   c:{name:'c'},
};

Object.keys(orig_obj).forEach((key) =>{
  orig_obj[key].newField = false;
});

console.log(orig_obj);
// Output:
/*
{
   a:{name:'a',newField:false},
   b:{name:'b',newField:false},
   c:{name:'c',newField:false},
}
*/