Group Javascript Items By One Property

My question is related to this question. You will have to first read it. var ids = '1*2*3'; var Name ='John*Brain*Andy'; var Code ='A12*B22*B22'; Now that I have an array of javas

Solution 1:

It is a little hard to tell the exact resulting structure that you want.

This code:

// Split values into arrays
Code = Code.split('*');
Name = Name.split('*');
ids = ids.split('*');

       // cache the length of one and create the result objectvarlength= Code.length;
varresult= {};

       // Iterate over each array item// If we come across a new code, //    add it to result with an empty arrayfor(vari=0; i < length; i++) {
    if(Code[i] inresult== false) {
        result[ Code[i] ] = [];
    }
            // Push a new object into the Code at "i" with the Name and ID at "i"
    result[ Code[i] ].push({ name:Name[i], id:ids[i] });
}

Will produce this structure:

// Resulting object
{
      // A12 has array with one object
    A12: [ {id: "1", name: "John"} ],

      // B22 has array with two objects
    B22: [ {id: "2", name: "Brain"},
           {id: "3", name: "Andy"}
         ]
}

Solution 2:

1. Split the strings on "*" so that you have 3 arrays.
2. Build objects from like-indexed elements of each array.
3. While building those objects, collect a second object that contains arrays for each "Code" value.

Code:

functiontoGroups(ids, names, codes) {
  ids = ids.split('*');
  names = names.split('*');
  codes = codes.split('*');
  if (ids.length !== names.length || ids.length !== codes.length)
    throw"Invalid strings";

  var objects = [], groupMap = {};
  for (var i = 0; i < ids.length; ++i) {
    var o = { id: ids[i], name: names[i], code: code[i] };
    objects.push(o);
    if (groupMap[o.code]) {
      groupMap[o.code].push(o);
    else
      groupMap[o.code] = [o];
  }
  return { objects: objects, groupMap: groupMap };
}

The "two arrays" you say you want will be in the "groupMap" property of the object returned by that function.