Map array values onto object key values-CodePudding

I have an object like this:

myObj = {
    prop1: 'prop1_value',
    prop2: 'prop2_value',
    subObj: {
        subProp1: 'subProp1_value',
        subProp2: 'subProp2_value',
        subProp3: 'subProp3_value',
        subprop4: 'subProp4_value',
    },
};

and an array like this:

myArr = [
    'arrayVal_1',
    'arrayVal_2',
    'arrayVal_3',
    'arrayVal_4',
];

For context, subObj and myArr always have the same length.

What I am trying to do is map each of the values from myArr onto the values of subObj.

myObj would look like this when done:

myObj = {
    prop1: 'prop1_value',
    prop2: 'prop2_value',
    subObj: {
        subProp1: 'arrayVal_1',
        subProp2: 'arrayVal_2',
        subProp3: 'arrayVal_3',
        subprop4: 'arrayVal_4',
    },
};

I could manually assign the values to each key individually, but that just seems sloppy. I've tried looping with Object.keys, Object.entries, and Object.values on myObj but just can't seem to reason through this one. Thanks.

CodePudding user response：

Using Object#keys and Array#forEach:

const 
  myObj = {
    prop1: 'prop1_value',
    prop2: 'prop2_value',
    subObj: { subProp1: 'subProp1_value', subProp2: 'subProp2_value', subProp3: 'subProp3_value', subprop4: 'subProp4_value' }
  },
  myArr = [ 'arrayVal_1', 'arrayVal_2', 'arrayVal_3', 'arrayVal_4' ];
  
const { subObj } = myObj;
Object.keys(subObj).forEach((prop, index) => { subObj[prop] = myArr[index] });

console.log(myObj);

CodePudding user response：

You could do it with Object.fromEntries and Object.keys this way:

myObj.subObj = Object.fromEntries(Object.keys(myObj.subObj).map((k,i) => [k, myArr[i]]))

Be aware there are currently no safe-guards of any kind, so you might want to check if the two datastructures fit, before doing this.

If you have something that you can order by object's keys by, you can also use sort to ensure you assign the correct values to the correct keys, because the resulting order of Object.keys is not guaranteed

 myObj.subObj = Object.fromEntries(Object.keys(myObj.subObj)
  .sort((a,b) => a.localeCompare(b)) //sort keys ascending by name 
  .map((k,i) => [k, myArr[i]]))

CodePudding user response：

You want to loop your keys and array together. One way is to try like this:

const myObj = {
    prop1: 'prop1_value',
    prop2: 'prop2_value',
    subObj: {
        subProp1: 'subProp1_value',
        subProp2: 'subProp2_value',
        subProp3: 'subProp3_value',
        subprop4: 'subProp4_value',
    },
};

const myArr = ['arrayVal_1', 'arrayVal_2', 'arrayVal_3', 'arrayVal_4'];

const keys = Object.keys(myObj.subObj); // You should actually sort these according to myArr to ensure safety

for (let i = 0; i < myArr.length; i  ) {
    myObj.subObj[keys[i]] = myArr[i];
}

console.log(myObj);