i have data in list object and datatable, how to join and retrive data

Riaz I

5y737Visual Basic .NET

4 Replies

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Rajanikant Hawaldar5y ago
Accepted answer
Hello Riaz I, Please check below code, if you have diffeculty to understand or have any question let us know.
using System;
using System.Collections.Generic;
using System.Data;
using System.Linq;
namespace DataTableJoinList
{
    class Program
    {
        class StdCode
        {
            public string STDCode { get; set; }
            public string Description { get; set; }
        }
        static void Main(string[] args)
        {
            DataTable dt = new DataTable();
            DataColumn dc = new DataColumn();
            dt.Columns.Add(new DataColumn("Code"));
            dt.Columns.Add(new DataColumn("Value"));
            dt.Columns.Add(new DataColumn("STDCode"));
            dt.Columns.Add(new DataColumn("Description"));

            DataRow row = dt.NewRow();
            row["Code"] = "code1";
            row["Value"] = "value1";
            row["STDCode"] = "abcd12";
            row["Description"] = "abcjkdh";
            dt.Rows.Add(row);

            row = dt.NewRow();
            row["Code"] = "code2";
            row["Value"] = "value2";
            row["STDCode"] = "cdfg34";
            row["Description"] = "cdfg34";
            dt.Rows.Add(row);

            List listCodes = new List()
            {
                new StdCode(){ STDCode = "abcd12", Description="sdfsd"},
                new StdCode(){ STDCode="fhry67", Description = "uisydif"}
            };

            var query = dt.AsEnumerable().
                                    Select(item => new
                                    {
                                        Code = item.Field<string>("Code"),
                                        Value = item.Field<string>("Value"),
                                        STDCode = item.Field<string>("STDCode"),
                                        Description = item.Field<string>("Description")
                                    });

            var query1 = listCodes.Join(query, x => x.STDCode, y => y.STDCode, (x, y) => y);

            Console.WriteLine("Code\tValue\tSTDCode\tDescription");
            foreach (var r in query1)
            {
                Console.WriteLine(string.Format("{0}\t{1}\t{2}\t{3}", r.Code, r.Value, r.STDCode, r.Description));
            }
            Console.ReadKey();
        }
    }
}
Mageshwaran R5y ago
Hi Riaz,
Please refer this link,

https://stackoverflow.com/questions/1412008/join-datatable-with-listsomeobject
Sachin Singh5y ago
why don't you simply convert your dataTable into List of Object that you already have, then do whatever you want with that List
Suppose You have a
List Students; And
DataTable with Student Data
simply convert DataTable to List and It will be more easy to use.
DataTable dt = new DataTable("Student");
    dt.Columns.Add("StudentId", typeof(Int32));
    dt.Columns.Add("StudentName", typeof(string));
    dt.Columns.Add("Address", typeof(string));
    dt.Columns.Add("MobileNo", typeof(string));
    //Data
    dt.Rows.Add(1, "Manish", "Hyderabad", "0000000000");
    dt.Rows.Add(2, "Venkat", "Hyderabad", "111111111");
    dt.Rows.Add(3, "Namit", "Pune", "1222222222");
    dt.Rows.Add(4, "Abhinav", "Bhagalpur", "3333333333");

    List studentList = new List();    // here you can use Old List
    for (int i = 0; i < dt.Rows.Count; i++)
    {
        Student student = new Student();
        student.StudentId = Convert .ToInt32 (dt.Rows[i]["StudentId"]);
        student.StudentName = dt.Rows[i]["StudentName"].ToString();
        student.Address = dt.Rows[i]["Address"].ToString();
        student.MobileNo = dt.Rows[i]["MobileNo"].ToString();
        studentList.Add(student);
    }
Riaz I5y ago
ok i'll check and comeback!