JAVASCRIPT - 从对象的父对象数组中获取值，在数组展平后的子对象中

Question

I have an Array of Objects, which has some values. Examples:

bigArray: [
  {
   greatName: 'Name String - #1',
   array: [{
     id: 1,
     name: 'string name - #1'
   }]
  },
  {
   greatName: 'Name String - #2',
   array: [{
     id: 2,
     name: 'string name - #2'
   }]
  },
  {
   greatName: 'Name String - #3',
   array: [{
     id: 3,
     name: 'string name - #3'
   }]
  }
]

I used the following composed functions from ramda, in order to get all Arrays array properties value and flatten them into a single array:

  const extractRB = compose(
    flatten,
    map(props(['array']))
  );

Which gave me back the following array:

// Flatten Array:
flatten: [
  {
     id: 1,
     name: 'string name - #1'
   },
   {
     id: 2,
     name: 'string name - #2'
   },
   {
     id: 3,
     name: 'string name - #3'
   }
]

Now, that is a requirement, for my feature. THE PROBLEM is I also need the greatName , property value inside each object, in order to map through them. But I cannot find a way to actually get the correct values inside the object..

What I want to achieve is this Array of Objects. Keep in mind that I can have dozens of Objects in Big Array, and hundrends of Objects inside each child array :

// Flatten Array:
flatten: [
  {
     id: 1,
     name: 'string name - #1'
     greatName: 'Name String - #1',
   },
   {
     id: 2,
     name: 'string name - #2',
     greatName: 'Name String - #2',
   },
   {
     id: 3,
     name: 'string name - #3',
     greatName: 'Name String - #3',
   }
]

I did this, which is spreading the original object from the flatten array and add the greatName property to it, but how to calculate which is the correct value for each object. There is no common value between the object and the array to condition on:

flatten.map(flatObj =>  {...flatObj, greatName: bigArray.map(// what operation can I do here, to get the correct value for each object inside the `bigArray` )});

I tried quite a few conditional operation, but they will always return false. Mayne there is a way to do it with the length of each array but not sure how to do it.

Help would be greatly appreciated..!! Thank you!!

Answer 1

 var bigArray= [ { greatName: 'Name String - #1', array: [{ id: 1, name: 'string name - #1' }] }, { greatName: 'Name String - #2', array: [{ id: 2, name: 'string name - #2' }] }, { greatName: 'Name String - #3', array: [{ id: 3, name: 'string name - #3' }] } ] console.log(bigArray.flatMap(({greatName, array}) => array.flatMap(x => ({greatName, ...x}))))

If array property always have only 1 element, so you can write it shorter:

  bigArray.map(({greatName, array}) => ({greatName, ...array[0]}))

Answer 2

Can you try this once, may be this will solve your problem:

bigArray.forEach((item)=>{
item.array.greatName  = item.greatName;
delete item.greatName;
})

Just console bigArray and don't use this and just try with above method

 const extractRB = compose(
    flatten,
    map(props(['array']))
  );