Hi alex0230,

Refer below modified code.

Namespaces

C#

using System.Data;
using System.IO;
using System.Linq;
using System.Text;
using System.Net;
using Newtonsoft.Json;

VB.Net

Imports System.Data
Imports System.IO
Imports System.Linq
Imports System.Text
Imports System.Net
Imports Newtonsoft.Json

Code

C#

protected void Page_Load(object sender, EventArgs e)
{
    List<Root> roots = JsonConvert.DeserializeObject<List<Root>>(File.ReadAllText(Server.MapPath("~/json.json")));
    DataTable dt = new DataTable();
    dt.Columns.Add("Name");
    dt.Columns.Add("Latitude");
    dt.Columns.Add("Longitude");
    dt.Columns.Add("Description");

    foreach (Root root in roots)
    {
        string CompName = "", addressLine = "", CompCity = "", CompState = "", CompZip = "";
        string description = "0";
        if (!string.IsNullOrEmpty(root.company.name))
        {
            CompName = root.company.name;
        }
        if (!string.IsNullOrEmpty(root.addressLine1))
        {
            addressLine = root.addressLine1;
        }
        if (!string.IsNullOrEmpty(root.city))
        {
            CompCity = root.city;
        }
        if (!string.IsNullOrEmpty(root.stateIdentifier))
        {
            CompState = root.stateIdentifier;
        }
        if (!string.IsNullOrEmpty(root.zip))
        {
            CompZip = root.zip;
        }

        string address = string.Format("{0}+{1}+{2}+{3}", addressLine.ToString(), CompCity.ToString(), CompState.ToString(), CompZip.ToString());
        if (!string.IsNullOrEmpty(address.Replace("+", "")))
        {
            double latitude = GetLatLon(address).Latitude;
            double longitude = GetLatLon(address).Longitude;

            dt.Rows.Add(CompName, latitude, longitude, description);
        }
    }

    var result = (from customer in dt.AsEnumerable()
                    group customer by customer["Name"] into g
                    orderby g.Count() descending
                    select g).Take(10);

    DataTable dtFinal = dt.Clone();
    foreach (var item in result)
    {
        DataRow dr = dt.Select("Name='" + item.Key + "'")[0];
        dtFinal.Rows.Add(dr.ItemArray);
    }
}

public LatLon GetLatLon(string address)
{
    string url = string.Format("https://maps.googleapis.com/maps/api/geocode/json?address={0}&key=API_Key", Server.UrlEncode(address));
    HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
    HttpWebResponse response = (HttpWebResponse)request.GetResponse();
    try
    {
        if (response.StatusCode == HttpStatusCode.OK)
        {
            MemoryStream ms = new MemoryStream();
            Stream responseStream = response.GetResponseStream();
            byte[] buffer = new byte[2049];
            int count = responseStream.Read(buffer, 0, buffer.Length);

            while (count > 0)
            {
                ms.Write(buffer, 0, count);
                count = responseStream.Read(buffer, 0, buffer.Length);
            }

            responseStream.Close();
            ms.Close();
            byte[] responseBytes = ms.ToArray();
            ASCIIEncoding encoding = new ASCIIEncoding();
            string coords = encoding.GetString(responseBytes);
            Root1 result = JsonConvert.DeserializeObject<Root1>(coords);
            if (result.results.Count > 0)
            {
                return new LatLon()
                {
                    Latitude = result.results[0].geometry.location.lat,
                    Longitude = result.results[0].geometry.location.lng
                };
            }
            else
            {
                return new LatLon() { };
            }
        }
    }
    catch (Exception ex)
    {
    }

    return new LatLon() { };
}

public class LatLon
{
    public double Latitude { get; set; }
    public double Longitude { get; set; }
}

public class AddressComponent
{
    public string long_name { get; set; }
    public string short_name { get; set; }
    public List<string> types { get; set; }
}

public class Geometry
{
    public Location1 location { get; set; }
    public string location_type { get; set; }
    public Viewport viewport { get; set; }
}

public class Location1
{
    public double lat { get; set; }
    public double lng { get; set; }
}

public class Northeast
{
    public double lat { get; set; }
    public double lng { get; set; }
}

public class PlusCode
{
    public string compound_code { get; set; }
    public string global_code { get; set; }
}

public class Result
{
    public List<AddressComponent> address_components { get; set; }
    public string formatted_address { get; set; }
    public Geometry geometry { get; set; }
    public string place_id { get; set; }
    public PlusCode plus_code { get; set; }
    public List<string> types { get; set; }
}

public class Root1
{
    public List<Result> results { get; set; }
    public string status { get; set; }
}

public class Southwest
{
    public double lat { get; set; }
    public double lng { get; set; }
}

public class Viewport
{
    public Northeast northeast { get; set; }
    public Southwest southwest { get; set; }
}

public class Agreement
{
    public int id { get; set; }
    public string name { get; set; }
    public Info _info { get; set; }
}

public class Board
{
    public int id { get; set; }
    public string name { get; set; }
    public Info _info { get; set; }
}

public class Company
{
    public int id { get; set; }
    public string identifier { get; set; }
    public string name { get; set; }
    public Info _info { get; set; }
}

public class Contact
{
    public int id { get; set; }
    public string name { get; set; }
    public Info _info { get; set; }
}

public class Country
{
    public int id { get; set; }
    public string name { get; set; }
    public Info _info { get; set; }
}

public class Currency
{
    public int id { get; set; }
    public string symbol { get; set; }
    public string currencyCode { get; set; }
    public string decimalSeparator { get; set; }
    public int numberOfDecimals { get; set; }
    public string thousandsSeparator { get; set; }
    public bool negativeParenthesesFlag { get; set; }
    public bool displaySymbolFlag { get; set; }
    public string currencyIdentifier { get; set; }
    public bool displayIdFlag { get; set; }
    public bool rightAlign { get; set; }
    public string name { get; set; }
    public Info _info { get; set; }
}

public class CustomField
{
    public int id { get; set; }
    public string caption { get; set; }
    public string type { get; set; }
    public string entryMethod { get; set; }
    public int numberOfDecimals { get; set; }
    public string value { get; set; }
}

public class Department
{
    public int id { get; set; }
    public string identifier { get; set; }
    public string name { get; set; }
    public Info _info { get; set; }
}

public class Info
{
    public string board_href { get; set; }
    public string priority_href { get; set; }
    public string image_href { get; set; }
    public string location_href { get; set; }
    public string source_href { get; set; }
    public string department_href { get; set; }
    public string sla_href { get; set; }
    public string currency_href { get; set; }
    public DateTime lastUpdated { get; set; }
    public string updatedBy { get; set; }
    public DateTime dateEntered { get; set; }
    public string enteredBy { get; set; }
    public string activities_href { get; set; }
    public string scheduleentries_href { get; set; }
    public string documents_href { get; set; }
    public string configurations_href { get; set; }
    public string tasks_href { get; set; }
    public string notes_href { get; set; }
    public string products_href { get; set; }
    public string timeentries_href { get; set; }
    public string expenseEntries_href { get; set; }
    public string agreement_href { get; set; }
    public string type_href { get; set; }
    public string status_href { get; set; }
    public string member_href { get; set; }
    public string workRole_href { get; set; }
    public string workType_href { get; set; }
    public string company_href { get; set; }
    public string mobileGuid { get; set; }
    public string site_href { get; set; }
    public string country_href { get; set; }
    public string contact_href { get; set; }
    public string team_href { get; set; }
}

public class Location
{
    public int id { get; set; }
    public string name { get; set; }
    public Info _info { get; set; }
}

public class Owner
{
    public int id { get; set; }
    public string identifier { get; set; }
    public string name { get; set; }
    public Info _info { get; set; }
}

public class Priority
{
    public int id { get; set; }
    public string name { get; set; }
    public int sort { get; set; }
    public Info _info { get; set; }
}

public class Root
{
    public int id { get; set; }
    public string summary { get; set; }
    public string recordType { get; set; }
    public Board board { get; set; }
    public Status status { get; set; }
    public WorkRole workRole { get; set; }
    public WorkType workType { get; set; }
    public Company company { get; set; }
    public Site site { get; set; }
    public string siteName { get; set; }
    public string addressLine1 { get; set; }
    public string city { get; set; }
    public string stateIdentifier { get; set; }
    public Country country { get; set; }
    public Contact contact { get; set; }
    public string contactName { get; set; }
    public string contactPhoneNumber { get; set; }
    public string contactEmailAddress { get; set; }
    public Team team { get; set; }
    public Priority priority { get; set; }
    public ServiceLocation serviceLocation { get; set; }
    public Source source { get; set; }
    public string severity { get; set; }
    public string impact { get; set; }
    public bool allowAllClientsPortalView { get; set; }
    public bool customerUpdatedFlag { get; set; }
    public bool automaticEmailContactFlag { get; set; }
    public bool automaticEmailResourceFlag { get; set; }
    public bool automaticEmailCcFlag { get; set; }
    public bool closedFlag { get; set; }
    public bool approved { get; set; }
    public double estimatedExpenseCost { get; set; }
    public double estimatedExpenseRevenue { get; set; }
    public double estimatedProductCost { get; set; }
    public double estimatedProductRevenue { get; set; }
    public double estimatedTimeCost { get; set; }
    public double estimatedTimeRevenue { get; set; }
    public string billingMethod { get; set; }
    public string subBillingMethod { get; set; }
    public int resolveMinutes { get; set; }
    public int resPlanMinutes { get; set; }
    public int respondMinutes { get; set; }
    public bool isInSla { get; set; }
    public bool hasChildTicket { get; set; }
    public bool hasMergedChildTicketFlag { get; set; }
    public string billTime { get; set; }
    public string billExpenses { get; set; }
    public string billProducts { get; set; }
    public Location location { get; set; }
    public Department department { get; set; }
    public string mobileGuid { get; set; }
    public Sla sla { get; set; }
    public Currency currency { get; set; }
    public Info _info { get; set; }
    public DateTime escalationStartDateUTC { get; set; }
    public int escalationLevel { get; set; }
    public int minutesBeforeWaiting { get; set; }
    public int respondedSkippedMinutes { get; set; }
    public int resplanSkippedMinutes { get; set; }
    public List<CustomField> customFields { get; set; }
    public string zip { get; set; }
    public Agreement agreement { get; set; }
    public string slaStatus { get; set; }
    public Type type { get; set; }
    public double? actualHours { get; set; }
    public string resources { get; set; }
    public bool? requestForChangeFlag { get; set; }
    public string automaticEmailCc { get; set; }
    public DateTime? dateResplan { get; set; }
    public DateTime? dateResponded { get; set; }
    public string addressLine2 { get; set; }
    public Owner owner { get; set; }
}

public class ServiceLocation
{
    public int id { get; set; }
    public string name { get; set; }
    public Info _info { get; set; }
}

public class Site
{
    public int id { get; set; }
    public string name { get; set; }
    public Info _info { get; set; }
}

public class Sla
{
    public int id { get; set; }
    public string name { get; set; }
    public Info _info { get; set; }
}

public class Source
{
    public int id { get; set; }
    public string name { get; set; }
    public Info _info { get; set; }
}

public class Status
{
    public int id { get; set; }
    public string name { get; set; }
    public Info _info { get; set; }
}

public class Team
{
    public int id { get; set; }
    public string name { get; set; }
    public Info _info { get; set; }
}

public class Type
{
    public int id { get; set; }
    public string name { get; set; }
    public Info _info { get; set; }
}

public class WorkRole
{
    public int id { get; set; }
    public string name { get; set; }
    public Info _info { get; set; }
}

public class WorkType
{
    public int id { get; set; }
    public string name { get; set; }
    public Info _info { get; set; }
}

VB.Net

Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs) Handles Me.Load
    Dim roots As List(Of Root) = JsonConvert.DeserializeObject(Of List(Of Root))(File.ReadAllText(Server.MapPath("~/json.json")))
    Dim dt As DataTable = New DataTable()
    dt.Columns.Add("Name")
    dt.Columns.Add("Latitude")
    dt.Columns.Add("Longitude")
    dt.Columns.Add("Description")

    For Each root As Root In roots
        Dim CompName As String = "", addressLine As String = "", CompCity As String = "", CompState As String = "", CompZip As String = ""
        Dim description As String = "0"

        If Not String.IsNullOrEmpty(root.company.name) Then
            CompName = root.company.name
        End If

        If Not String.IsNullOrEmpty(root.addressLine1) Then
            addressLine = root.addressLine1
        End If

        If Not String.IsNullOrEmpty(root.city) Then
            CompCity = root.city
        End If

        If Not String.IsNullOrEmpty(root.stateIdentifier) Then
            CompState = root.stateIdentifier
        End If

        If Not String.IsNullOrEmpty(root.zip) Then
            CompZip = root.zip
        End If

        Dim address As String = String.Format("{0}+{1}+{2}+{3}", addressLine.ToString(), CompCity.ToString(), CompState.ToString(), CompZip.ToString())

        If Not String.IsNullOrEmpty(address.Replace("+", "")) Then
            Dim latitude As Double = GetLatLon(address).Latitude
            Dim longitude As Double = GetLatLon(address).Longitude
            dt.Rows.Add(CompName, latitude, longitude, description)
        End If
    Next

    Dim result = (From customer In dt.AsEnumerable()
                    Group customer By Key = customer("Name") Into grp = Group
                    Order By grp.Count() Descending
                    Select grp).Take(10)

    Dim dtFinal As DataTable = dt.Clone()

    For Each item In result
        Dim dr As DataRow = dt.Select("Name='" & DirectCast(item, DataRow())(0)("Name") & "'")(0)
        dtFinal.Rows.Add(dr.ItemArray)
    Next
End Sub

Public Function GetLatLon(ByVal address As String) As LatLon
    Dim url As String = String.Format("https://maps.googleapis.com/maps/api/geocode/json?address={0}&key=API_Key", Server.UrlEncode(address))
    Dim request As HttpWebRequest = CType(WebRequest.Create(url), HttpWebRequest)
    Dim response As HttpWebResponse = CType(request.GetResponse(), HttpWebResponse)
    Try
        If response.StatusCode = HttpStatusCode.OK Then
            Dim ms As MemoryStream = New MemoryStream()
            Dim responseStream As Stream = response.GetResponseStream()
            Dim buffer As Byte() = New Byte(2048) {}
            Dim count As Integer = responseStream.Read(buffer, 0, buffer.Length)

            While count > 0
                ms.Write(buffer, 0, count)
                count = responseStream.Read(buffer, 0, buffer.Length)
            End While

            responseStream.Close()
            ms.Close()
            Dim responseBytes As Byte() = ms.ToArray()
            Dim encoding As ASCIIEncoding = New ASCIIEncoding()
            Dim coords As String = encoding.GetString(responseBytes)
            Dim result As Root1 = JsonConvert.DeserializeObject(Of Root1)(coords)

            If result.results.Count > 0 Then
                Return New LatLon() With {
                .Latitude = result.results(0).geometry.location.lat,
                .Longitude = result.results(0).geometry.location.lng
            }
            Else
                Return New LatLon()
            End If
        End If

    Catch ex As Exception
    End Try

    Return New LatLon()
End Function

Public Class LatLon
    Public Property Latitude As Double
    Public Property Longitude As Double
End Class

Public Class AddressComponent
    Public Property long_name As String
    Public Property short_name As String
    Public Property types As List(Of String)
End Class

Public Class Geometry
    Public Property location As Location1
    Public Property location_type As String
    Public Property viewport As Viewport
End Class

Public Class Location1
    Public Property lat As Double
    Public Property lng As Double
End Class

Public Class Northeast
    Public Property lat As Double
    Public Property lng As Double
End Class

Public Class PlusCode
    Public Property compound_code As String
    Public Property global_code As String
End Class

Public Class Result
    Public Property address_components As List(Of AddressComponent)
    Public Property formatted_address As String
    Public Property geometry As Geometry
    Public Property place_id As String
    Public Property plus_code As PlusCode
    Public Property types As List(Of String)
End Class

Public Class Root1
    Public Property results As List(Of Result)
    Public Property status As String
End Class

Public Class Southwest
    Public Property lat As Double
    Public Property lng As Double
End Class

Public Class Viewport
    Public Property northeast As Northeast
    Public Property southwest As Southwest
End Class

Public Class Agreement
    Public Property id As Integer
    Public Property name As String
    Public Property _info As Info
End Class

Public Class Board
    Public Property id As Integer
    Public Property name As String
    Public Property _info As Info
End Class

Public Class Company
    Public Property id As Integer
    Public Property identifier As String
    Public Property name As String
    Public Property _info As Info
End Class

Public Class Contact
    Public Property id As Integer
    Public Property name As String
    Public Property _info As Info
End Class

Public Class Country
    Public Property id As Integer
    Public Property name As String
    Public Property _info As Info
End Class

Public Class Currency
    Public Property id As Integer
    Public Property symbol As String
    Public Property currencyCode As String
    Public Property decimalSeparator As String
    Public Property numberOfDecimals As Integer
    Public Property thousandsSeparator As String
    Public Property negativeParenthesesFlag As Boolean
    Public Property displaySymbolFlag As Boolean
    Public Property currencyIdentifier As String
    Public Property displayIdFlag As Boolean
    Public Property rightAlign As Boolean
    Public Property name As String
    Public Property _info As Info
End Class

Public Class CustomField
    Public Property id As Integer
    Public Property caption As String
    Public Property type As String
    Public Property entryMethod As String
    Public Property numberOfDecimals As Integer
    Public Property value As String
End Class

Public Class Department
    Public Property id As Integer
    Public Property identifier As String
    Public Property name As String
    Public Property _info As Info
End Class

Public Class Info
    Public Property board_href As String
    Public Property priority_href As String
    Public Property image_href As String
    Public Property location_href As String
    Public Property source_href As String
    Public Property department_href As String
    Public Property sla_href As String
    Public Property currency_href As String
    Public Property lastUpdated As DateTime
    Public Property updatedBy As String
    Public Property dateEntered As DateTime
    Public Property enteredBy As String
    Public Property activities_href As String
    Public Property scheduleentries_href As String
    Public Property documents_href As String
    Public Property configurations_href As String
    Public Property tasks_href As String
    Public Property notes_href As String
    Public Property products_href As String
    Public Property timeentries_href As String
    Public Property expenseEntries_href As String
    Public Property agreement_href As String
    Public Property type_href As String
    Public Property status_href As String
    Public Property member_href As String
    Public Property workRole_href As String
    Public Property workType_href As String
    Public Property company_href As String
    Public Property mobileGuid As String
    Public Property site_href As String
    Public Property country_href As String
    Public Property contact_href As String
    Public Property team_href As String
End Class

Public Class Location
    Public Property id As Integer
    Public Property name As String
    Public Property _info As Info
End Class

Public Class Owner
    Public Property id As Integer
    Public Property identifier As String
    Public Property name As String
    Public Property _info As Info
End Class

Public Class Priority
    Public Property id As Integer
    Public Property name As String
    Public Property sort As Integer
    Public Property _info As Info
End Class

Public Class Root
    Public Property id As Integer
    Public Property summary As String
    Public Property recordType As String
    Public Property board As Board
    Public Property status As Status
    Public Property workRole As WorkRole
    Public Property workType As WorkType
    Public Property company As Company
    Public Property site As Site
    Public Property siteName As String
    Public Property addressLine1 As String
    Public Property city As String
    Public Property stateIdentifier As String
    Public Property country As Country
    Public Property contact As Contact
    Public Property contactName As String
    Public Property contactPhoneNumber As String
    Public Property contactEmailAddress As String
    Public Property team As Team
    Public Property priority As Priority
    Public Property serviceLocation As ServiceLocation
    Public Property source As Source
    Public Property severity As String
    Public Property impact As String
    Public Property allowAllClientsPortalView As Boolean
    Public Property customerUpdatedFlag As Boolean
    Public Property automaticEmailContactFlag As Boolean
    Public Property automaticEmailResourceFlag As Boolean
    Public Property automaticEmailCcFlag As Boolean
    Public Property closedFlag As Boolean
    Public Property approved As Boolean
    Public Property estimatedExpenseCost As Double
    Public Property estimatedExpenseRevenue As Double
    Public Property estimatedProductCost As Double
    Public Property estimatedProductRevenue As Double
    Public Property estimatedTimeCost As Double
    Public Property estimatedTimeRevenue As Double
    Public Property billingMethod As String
    Public Property subBillingMethod As String
    Public Property resolveMinutes As Integer
    Public Property resPlanMinutes As Integer
    Public Property respondMinutes As Integer
    Public Property isInSla As Boolean
    Public Property hasChildTicket As Boolean
    Public Property hasMergedChildTicketFlag As Boolean
    Public Property billTime As String
    Public Property billExpenses As String
    Public Property billProducts As String
    Public Property location As Location
    Public Property department As Department
    Public Property mobileGuid As String
    Public Property sla As Sla
    Public Property currency As Currency
    Public Property _info As Info
    Public Property escalationStartDateUTC As DateTime
    Public Property escalationLevel As Integer
    Public Property minutesBeforeWaiting As Integer
    Public Property respondedSkippedMinutes As Integer
    Public Property resplanSkippedMinutes As Integer
    Public Property customFields As List(Of CustomField)
    Public Property zip As String
    Public Property agreement As Agreement
    Public Property slaStatus As String
    Public Property type As Type
    Public Property actualHours As Double?
    Public Property resources As String
    Public Property requestForChangeFlag As Boolean?
    Public Property automaticEmailCc As String
    Public Property dateResplan As DateTime?
    Public Property dateResponded As DateTime?
    Public Property addressLine2 As String
    Public Property owner As Owner
End Class

Public Class ServiceLocation
    Public Property id As Integer
    Public Property name As String
    Public Property _info As Info
End Class

Public Class Site
    Public Property id As Integer
    Public Property name As String
    Public Property _info As Info
End Class

Public Class Sla
    Public Property id As Integer
    Public Property name As String
    Public Property _info As Info
End Class

Public Class Source
    Public Property id As Integer
    Public Property name As String
    Public Property _info As Info
End Class

Public Class Status
    Public Property id As Integer
    Public Property name As String
    Public Property _info As Info
End Class

Public Class Team
    Public Property id As Integer
    Public Property name As String
    Public Property _info As Info
End Class

Public Class Type
    Public Property id As Integer
    Public Property name As String
    Public Property _info As Info
End Class

Public Class WorkRole
    Public Property id As Integer
    Public Property name As String
    Public Property _info As Info
End Class

Public Class WorkType
    Public Property id As Integer
    Public Property name As String
    Public Property _info As Info
End Class

Screenshot