将数组添加为新的键值对

Question

I have an existing array which contains key-value pairs for a series of items:

resultsArray = [
  {
    parkName: "Central Park",
    owner: "NYC" 
  },
  {
    parkName: "Patterson Park",
    owner: "Baltimore"
  }
]

I'd like to add an additional key-value pair to each item where the value is an array of amenities. For example: if Central Park includes a dog park, jogging trail, and basketball courts, and Patterson Park includes a baseball field and a rec center, when the amenities were added to the array, the resultsArray would now look like:

resultsArray = [
  {
    parkName: "Central Park",
    owner: "NYC",
    amenities: "Dog Park", "Jogging Trail", "Basketball Courts"
   },
  {
    parkName: "Patterson Park",
    owner: "Baltimore",
    amenities: "Baseball Fields", "Recreation Center"
   }
]

I'm relatively new to Javascript, but I've successfully created an array of amenities for each of the parks. I then tried to add each amenityArray as follows:

resultsArray.push({
  amenities: amenityArray
});

However, this didn't give me what I wanted.

Can someone demonstrate how I would add the amenityArray as a key-value pair for each of the parks?

Answer 1

For each object in resultsArray , add the corresponding amenity.

for (let i = 0; i < resultsArray.length; i++) {
    resultsArray[i][i]['amenities'] = amenityArray[i];
}

A more verbose version would be

for (let i = 0; i < resultsArray.length; i++) {
    let result = resultsArray[i];  // i is an index
    let innerResult = result[i];  // i is a key
    innerResult['amenities'] = amenityArray[i];
}

Answer 2

Iterate the array and add a new key-value pair in the inner objects.

Note: Picked the amenities dynamically.

 resultsArray = [{ 0: { parkName: "Central Park", owner: "NYC" } }, { 1: { parkName: "Patterson Park", owner: "Baltimore" } }]; amenities = { "0": "X Park, Y Park, Z Park", "1": "A Park, B park, C Park" }; [...resultsArray].forEach(token => { Object.keys(token).forEach(key => token[key]['amenities'] = amenities[key]); }) console.log(resultsArray); 

Answer 3

You can use .forEach() to loop through the array and set each item depend on index:

 var resultsArray = [{parkName: "Central Park",owner: "NYC"},{parkName: "Patterson Park", owner: "Baltimore"}] var amenityArray = [["Dog Park", "Jogging Trail", "Basketball Courts"], ["Baseball Fields", "Recreation Center"]]; resultsArray.forEach((val, index) => {val.amenities = amenityArray[index]}) console.log(resultsArray) 

Answer 4

You can use map for this:

const newArray = resultsArray.map((item, i) => {
  item[i].amenities = amenityArray[i];
  return item;
});

Also your array structure looks weird, you should consider removing those redundant nested objects, and then it will be easier to iterate:

resultsArray = [{
    parkName: "Central Park",
    owner: "NYC"
  },
  {
    parkName: "Patterson Park",
    owner: "Baltimore"
  }
]

const newArray = resultsArray.map((item, i) => {
  item.amenities = amenityArray[i];
  return item;
});