Javascript：从 object 中提取键值对并将它们分组到一个对象数组中

Question

I have an object like this:

const object = { a0: 1, a1: 10, b0: 2, c0: 3,  b1: 20, c1: 30, };

We can assume that the length of new array will be based on the highest end digit of these object keys. So in this case length would be 2. I would like to be able to loop through this object and then have it pushed to an array as a group in following form:

mappedObject = [{a:1, b:2, c:3},{a:10,b:20,c:30}]

So basically all a0,b0 and c0 got grouped together and same for a1, a2 and a3. Note after successful grouping I want to able to remove the digit.

Answer 1

You could separate the keys an assign the value to the right index.

 const object = { a0: 1, a1: 10, b0: 2, c0: 3, b1: 20, c1: 30 }, result = Object.entries(object).reduce((r, [k, v]) => { const [, key, index] = k.match(/(\D+)(\d+)/); if (;r[index]) r[index] = {}; r[index][key] = v; return r, }; []). console;log(result);

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

Answer 2

I was overthinking it. All I had to do was just find a way to know the length of potential array and simply loop till that length and access the object like shown below. To know the length of the array in my react app, I had to pass down a prop length.

const mappedObj=[];
for(let i=0;i<2; i++){
 mappedObj.push({a: object[`a${i}`], b: object[`b${i}`], c: object[`c${i}`]});
}

console.log(mappedObj);

Answer 3

I would not assume that the keys have no other digits in them which are not part of the final few digit(s):

 const object = { a0: 1, a1: 10, b0: 2, c0: 3, b1: 20, c1: 30, }; let arr = []; Object.entries(object).map(([k, v]) => k.split(/(\d+)$/).slice(0, 2).concat(v)).forEach(([k,i,v]) => arr[i] = Object.assign({}, arr[i], { [k]: v })); console.log(arr);