Array.map函数不适用于Object值

Question

I'm attempting to re-map an Object that comes from an API call. The format of the response is the following:

data: {
    foo: [{
        id: "1",
        name: "joe",
        info: "whatever"
    }, {
        id: "2",
        name: "anna",
        info: "whatever"
    },...],
    bar: [...]
}

The code I'm using to re-map the object inside each response array is:

const DATA = response.data;
const entries = Object.entries(DATA);

for (const entry of entries) {
    entry[1].map(entry => ({
        id: entry["id"],
        mixed_info: entry["name"] + ", " + entry["info"]
    }));
}

When I console.log the data after this, it shows the same as the initial response, as if it completly ignored the map function.

What am I doing wrong? Thanks for the attention.

Answer 1

map 返回一个新数组，你忽略了调用的结果。

Answer 2

Assign the result of the map call:

entry[1] = entry[1].map(...);

Array.prototype.map returns a new array - it doesn't modify the original.

Answer 3

You have to reassign the entry :

  entry[1] = entry[1].map(/*...*/);

However that will only get reflected to the array inside entries , it won't change DATA . To change that, you have to either turn the key value pairs back into an object at the end:

  DATA = Object.fromEntries(entries);

Or you have to reassign the DATA properties while iterating:

   DATA[ entry[0] ] = entry[1].map(/*...*/);

---

I'd do:

  const { data } = response;

  for(const [key, value] of Object.entries(data)) {
     data[key] = value.map(/*...*/);
  }

Answer 4

    let result = {};
    for (const entry of entries) {
        result[entry[0]] = entry[1].map(entry => ({
            id: entry.id,
            mixed_info: `${entry["name"]  }, ${  entry["info"]}`,
        }));
    }

'result' contains exact remapped object.