CODEWITHSUNDEEP
linqc#-4.0
Python
Python

Reputation: 63

How to create a tree list from a list

I am stuck in converting a normal list to tree type list. I have to convert like below format: Can we create a list of parent child relationship?

State
 County
   Name
   Name2
 County
   Name3
   Name4

And below is my list :

{
    "data": [  
        {
            "name": "D1",
            "stateName": "Georgia",
            "stateId": 1,
            "countyName": "Apache",
            "countyId": 1
        },
        {
            "name": "D2",
            "stateName": "Georgia",
            "stateId": 1,
            "countyName": "Apache",
            "countyId": 1
        },
        {
            "name": "D3",
            "stateName": "Georgia",
            "stateId": 1,
            "countyName": "Apache",
            "countyId": 1
        },
        {
            "name": "D4",
            "stateName": "Georgia",
            "stateId": 1,
            "countyName": "Apache",
            "countyId": 1
        },
        {
            "name": "D5",
            "stateName": "Georgia",
            "stateId": 1,
            "countyName": "Catron",
            "countyId": 2
        }   
    ],
    "totalRowCount": 0,
    "errors": []
}

Is there any way that I can have tree list. Any help will be appreciated.

I am using below code for tree list but it is not giving me right data.

var lstTaxLocation = (from loc in _queryEntities.TaxLocations
                                  join st in _queryEntities.States on loc.StateId equals st.Id
                                  join cou in _queryEntities.Counties on loc.CountyId equals cou.Id
                                  group new { loc, st, cou } by new { st.Id } into pg
                                  let datagroup = pg.FirstOrDefault()
                                  let location = datagroup.loc
                                  let state = datagroup.st
                                  let county = datagroup.cou
                                  select new TaxLocationDto
                                  {
                                      Name = location.Name,
                                      StateId = state.Id,
                                      StateName = state.Name,
                                      CountyName = county.Name,
                                      CountyId = county.Id
                                  });

Upvotes: 1

Views: 80

Answers (1)

krillgar
krillgar

Reputation: 12805

This is very simple to do with LINQ.

Suppose you have your data already deserialized into C# objects:

public class Data
{
    public string Name { get; set; }
    public string StateName { get; set; }
    public int StateId { get; set; }
    public string CountyName { get; set; }
    public int CountyId { get; set; }
}

You can then use LINQ's GroupBy and SelectMany.

var treeList = data.GroupBy(d => d.StateName)
                   .SelectMany(group => group.GroupBy(d => d.CountyName));

This will give you the structure you're looking for, but each "node" will be the entire object, not just the Name property. You can get that as well if need be, but having the entire object there will most likely help more than just a single property.

Upvotes: 1

Related Questions