using System;

using System.Collections.Generic;   

using System.Text;

public class Program

{

    public static void Main()

    {

        List<MeetingTypeModel> list = new List<MeetingTypeModel>();

        list.Add(new MeetingTypeModel("1", "abc"));

        list.Add(new MeetingTypeModel("2", "xyz"));

        Program p = new Program();

        Console.WriteLine(p.GetString(list));

    }

    public string GetString(List<MeetingTypeModel> MeetingTypeList)

    {

    StringBuilder sb = new StringBuilder();

    sb.Append("({");

    int i = 1;

    foreach(MeetingTypeModel item in MeetingTypeList){

​

        sb.AppendFormat("\"{0}\" : \"{1}\"" , item.MeetingTypeId, item.MeetingTypeName);

        //To not append last comma

        if(i != MeetingTypeList.Count)

            sb.Append(",");

        i++;

    }

    sb.Append("})");

    return sb.ToString();

    }

    public class MeetingTypeModel

    {

        public string MeetingTypeId { get; set; }

        public string MeetingTypeName { get; set; }

        public MeetingTypeModel(string id, string name){

            MeetingTypeId = id;

            MeetingTypeName = name;

        }

    }

}