Dynamically forming array of object using given List

Question

Inputs1

var aa = [
   {
      "id":1,
      "name":"ajai",
      "country":"india",
      "qualification":"BE",
      "age":23
   },
   {
      "id":2,
      "name":"aravindh",
      "country":"india",
      "qualification":"BCOM",
      "age":24
   },
   {
      "id":3,
      "name":"gopal",
      "country":"china",
      "qualification":"MA",
      "age":23
   },
   {
      "id":4,
      "name":"guvaliour",
      "country":"china",
      "qualification":"BE",
      "age":24
   },
   {
      "id":5,
      "name":"anavarthan",
      "country":"japan",
      "qualification":"BE",
      "age":25
   },
   {
      "id":6,
      "name":"veer",
      "country":"china",
      "qualification":"MA",
      "age":23
   },
   {
      "id":7,
      "name":"ramani",
      "country":"india",
      "qualification":"BE",
      "age":23
   },
   {
      "id":8,
      "name":"kumar",
      "country":"india",
      "qualification":"MBA",
      "age":23
   }
]

Input2

 var bb = ['country','age','qualification']

Based on the both inputs i want to form the array of object using this required format.

Required Format:

[
   {
      "id":"india",
      "children":[
         {
            "id":"23",
            "children":[
               {
                  "id":"BE",
                  "children":[

                  ],
                  "dataSet":[
                     {
                        "id":1,
                        "name":"ajai",
                        "country":"india",
                        "qualification":"BE",
                        "age":23
                     },
                     {
                        "id":7,
                        "name":"ramani",
                        "country":"india",
                        "qualification":"BE",
                        "age":23
                     }
                  ]
               },
               {
                  "id":"MBA",
                  "children":[

                  ],
                  "dataSet":[
                     {
                        "id":8,
                        "name":"kumar",
                        "country":"india",
                        "qualification":"MBA",
                        "age":23
                     }
                  ]
               }
            ]
         },
         {
            "id":"24",
            "children":[
               {
                  "id":"BCOM",
                  "children":[

                  ],
                  "dataSet":[
                     {
                        "id":2,
                        "name":"aravindh",
                        "country":"india",
                        "qualification":"BCOM",
                        "age":24
                     }
                  ]
               }
            ]
         }
      ]
   },
   {
      "id":"china",
      "children":[
         {
            "id":"23",
            "children":[
               {
                  "id":"MA",
                  "children":[

                  ],
                  "dataSet":[
                     {
                        "id":6,
                        "name":"veer",
                        "country":"china",
                        "qualification":"MA",
                        "age":23
                     },
                     {
                        "id":3,
                        "name":"gopal",
                        "country":"china",
                        "qualification":"MA",
                        "age":23
                     }
                  ]
               }
            ]
         },
         {
            "id":"24",
            "children":[
               {
                  "id":"BE",
                  "children":[

                  ],
                  "dataSet":[
                     {
                        "id":4,
                        "name":"guvaliour",
                        "country":"china",
                        "qualification":"BE",
                        "age":24
                     }
                  ]
               }
            ]
         }
      ]
   },
   {
      "id":"japan",
      "children":[
         {
            "id":"25",
            "children":[
               {
                  "id":"BE",
                  "children":[

                  ],
                  "dataSet":[
                     {
                        "id":5,
                        "name":"anavarthan",
                        "country":"japan",
                        "qualification":"BE",
                        "age":25
                     }
                  ]
               }
            ]
         }
      ]
   }
]

I have just tried to form this required format using the input 1 and input 2 but i struggled for a day.Please some one can help me out to solve this issue. I'm using this tree to form a grouping table in Angular 6.This is some what like recursive.

something i have tried like this

    var dd=[];
    var aa = [
      {
         "id":1,
         "name":"ajai",
         "country":"india",
         "qualification":"BE",
         "age":23
      },
      {
         "id":2,
         "name":"aravindh",
         "country":"india",
         "qualification":"BCOM",
         "age":24
      },
      {
         "id":3,
         "name":"gopal",
         "country":"china",
         "qualification":"MA",
         "age":23
      },
      {
         "id":4,
         "name":"guvaliour",
         "country":"china",
         "qualification":"BE",
         "age":24
      },
      {
         "id":5,
         "name":"anavarthan",
         "country":"japan",
         "qualification":"BE",
         "age":25
      },
      {
         "id":6,
         "name":"veer",
         "country":"china",
         "qualification":"MA",
         "age":23
      },
      {
         "id":7,
         "name":"ramani",
         "country":"india",
         "qualification":"BE",
         "age":23
      },
      {
         "id":8,
         "name":"kumar",
         "country":"india",
         "qualification":"MBA",
         "age":23
      }
   ];
   var bb = ['country','age','qualification'];
   for(var i=0;i<aa.length;i++){
      for(var j=0;j<bb.length;j++){
        dd.push(this.formingArr(aa[i][bb[j]]))
      }
     }
     console.log(dd);
  }

  formingArr(value){
    let obj={
      id:value,
      children:[],
      dataSet:[]
    }
      return obj;
  }

my Output:

[
  {
    "id": "india",
    "children": [],
    "dataSet": []
  },
  {
    "id": 23,
    "children": [],
    "dataSet": []
  },
  {
    "id": "BE",
    "children": [],
    "dataSet": []
  },
  {
    "id": "india",
    "children": [],
    "dataSet": []
  },
  {
    "id": 24,
    "children": [],
    "dataSet": []
  },
  {
    "id": "BCOM",
    "children": [],
    "dataSet": []
  },
  {
    "id": "china",
    "children": [],
    "dataSet": []
  },
  {
    "id": 23,
    "children": [],
    "dataSet": []
  },
  {
    "id": "MA",
    "children": [],
    "dataSet": []
  },
  {
    "id": "china",
    "children": [],
    "dataSet": []
  },
  {
    "id": 24,
    "children": [],
    "dataSet": []
  },
  {
    "id": "BE",
    "children": [],
    "dataSet": []
  },
  {
    "id": "japan",
    "children": [],
    "dataSet": []
  },
  {
    "id": 25,
    "children": [],
    "dataSet": []
  },
  {
    "id": "BE",
    "children": [],
    "dataSet": []
  },
  {
    "id": "china",
    "children": [],
    "dataSet": []
  },
  {
    "id": 23,
    "children": [],
    "dataSet": []
  },
  {
    "id": "MA",
    "children": [],
    "dataSet": []
  },
  {
    "id": "india",
    "children": [],
    "dataSet": []
  },
  {
    "id": 23,
    "children": [],
    "dataSet": []
  },
  {
    "id": "BE",
    "children": [],
    "dataSet": []
  },
  {
    "id": "india",
    "children": [],
    "dataSet": []
  },
  {
    "id": 23,
    "children": [],
    "dataSet": []
  },
  {
    "id": "MBA",
    "children": [],
    "dataSet": []
  }
]

Show the code you tried with, it will probably get more people to help you rather than just showing the data and hoping for someone to write the code for you — Jay
– Jay, Commented Mar 11, 2020 at 1:19
I am not sure if i understand correctly, each object in your array looks like a trie. You could probably try to do it in the way similar to trie. — Andy Mok
– Andy Mok, Commented Mar 11, 2020 at 9:35

trincot · Accepted Answer · 2020-03-11 10:54:39Z

You could use a nested Map to create the tree structure, and then iterate that tree recursively to translate those maps to the plain, nested array of objects:

function transform(data, props) {
    // A recursive function to translate nested maps to plain objects/arrays
    const recur = (map, depth) => Array.from(map, ([id, value]) => depth ? {
        id,
        children: recur(value, depth - 1)
    } : {
        id,
        children: [],
        dataSet: Array.from(value.values())
    });

    // First create a nested Map to efficiently create the tree
    let result = new Map;
    for (let obj of data) {
        let map = result;
        for (let prop of props) {
            let key = obj[prop];
            let children = map.get(key);
            if (!children) map.set(key, children = new Map);
            map = children;
        }
        map.set(map.size, obj); // Deepest level is array-like
    }
    // Use recursion to convert the nested Map to the desired object structure
    return recur(result, props.length - 1);
}

// Demo on sample data
var aa = [{"id":1,"name":"ajai","country":"india","qualification":"BE","age":23},{"id":2,"name":"aravindh","country":"india","qualification":"BCOM","age":24},{"id":3,"name":"gopal","country":"china","qualification":"MA","age":23},{"id":4,"name":"guvaliour","country":"china","qualification":"BE","age":24},{"id":5,"name":"anavarthan","country":"japan","qualification":"BE","age":25},{"id":6,"name":"veer","country":"china","qualification":"MA","age":23},{"id":7,"name":"ramani","country":"india","qualification":"BE","age":23},{"id":8,"name":"kumar","country":"india","qualification":"MBA","age":23}];

var bb = ['country','age','qualification']

console.log(transform(aa, bb));

Ajai · Accepted Answer · 2020-05-25 00:12:38Z

var aa = [{"id":1,"name":"ajai","country":"india","qualification":"BE","age":23},{"id":2,"name":"aravindh","country":"india","qualification":"BCOM","age":24},{"id":3,"name":"gopal","country":"china","qualification":"MA","age":23},{"id":4,"name":"guvaliour","country":"china","qualification":"BE","age":24},{"id":5,"name":"anavarthan","country":"japan","qualification":"BE","age":25},{"id":6,"name":"veer","country":"china","qualification":"MA","age":23},{"id":7,"name":"ramani","country":"india","qualification":"BE","age":23},{"id":8,"name":"kumar","country":"india","qualification":"MBA","age":23}];

  var bb=[];
    var cc = ['country','age','qualification'];
    for(var i=0;i<=aa.length-1;i++){
      cc.reduce((acc,ele,index)=>{
        let obj={
          id: ele,
          name: aa[i][ele],
          children:[],
          dataSet: []
        }
        let pos = acc.map(ele=>ele.name).indexOf(aa[i][ele]);
        let ind = 0;
        if(pos == -1){
         acc.push(obj);
         ind = acc.length-1 < 0 ? 0 : acc.length-1;
        }else{
         ind=pos;
        }
        return acc[ind]['children'];
      },bb)
    }
    console.log(bb)

Collectives™ on Stack Overflow

Dynamically forming array of object using given List

2 Answers 2

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related