generate multilevel object from array in javascript

Question

I have a array of events and i want to make relation between these array's object. array:

[{
    'area': 'punjab',
    'site': 'lahore',
    'link': 'http: //lahore.com'
}, {
    'area': 'punjab',
    'site': 'sargodha',
    'link': 'http: //sargodha.com'
}, {
    'area': 'punjab',
    'site': 'multan',
    'link': 'http: //multan.com'
} {
    'area': 'sindh',
    'site': 'karachi',
    'link': 'http: //karachi.com'
}]

Know i want to make the relation like

 {
  "area": "punjab",
  "site": [
    {
      "name": "lahore",
      "link": [
        {
          "name": "http://sargodha.com",
        }
      ]
    },
   {
      "name": "sargodha",
      "link": [
        {
          "name": "http://sargodha.com",
        }
      ]
    }
  ]
},
{
  "area": "sindh",
  "site": [
    {
      "name": "karachi",
      "link": [
        {
          "name": "http://karachi.com",
        }
      ]
    }
}

here is my code which i wrote:

    function isinarrayfilters(matchingObject, targetArray, key) {
    var existindex = -1;
    $.each(targetArray, function(index, array) {
        if (array.key == matchingObject.key) {
            //Object exist in array
            existindex = index;
        }
    });
    return existindex;
}

generatedRelationArray = [];
        $.each(alertsJson, function(index, alertJson) {
            inarrayindex = isinarrayfilters(alertJson.area, relationArray,'area');
            if (inarrayindex == -1) {
                key = alertJson.site
                generatedsites = {
                    "area": alertJson.area,
                    "site": []
                }
                relationArray.push(generatedsites);
            }
        });

Know anyone guide me how i append the site into the related area.

• I have to run loop again and try to check the exist method and get the index and will push the sites into it?

Answer 1

A Format preserved answer:

var generate = function(list) {
  var resultList = [];
  var tmpStoreRef = {};

  $.each(list, function(id, item) {
    var area = item.area
        ,site = item.site
        ,link = item.link;
    if (typeof tmpStoreRef[area] === 'undefined') {
      tmpStoreRef[area] = {
        area: area,
        site: []
      }
      resultList.push(tmpStoreRef[area]);
    }
    tmpStoreRef[area].site.push({
      name: site,
      link: link
    });
  });

  return resultList;
};

Answer 2

You can use query-js to accomplish this

Assuming your original array is stored in data

var res = data.groupBy(function(e){ return e.area; });

That would create a slightly different structure:

{
  "punjab" : [{
     'area': 'punjab',
     'site': 'lahore',
     'link': 'http: //lahore.com'
   }, {
     'area': 'punjab',
     'site': 'sargodha',
     'link': 'http: //sargodha.com'
   }, {
     'area': 'punjab',
     'site': 'multan',
     'link': 'http: //multan.com'
  }],
 "sindh": [...]
}

If you need that explicit structure then you can do this instead

var res = data.groupBy(function(e){ return e.area; })
              .each(function(e){
                  return {
                           area : e.key,
                           site : e.value.select(function(e){
                                return {
                                     name : e.site,
                                     linkm : [e.link]
                                };
                           });
              });

I've created a post that's supposed to be explanatory of what query-js is and how to use it