WCF

create a wcf service->write below code in interface

using System;
using System.Collections.Generic;
using System.Data;
using System.Linq;
using System.Runtime.Serialization;
using System.ServiceModel;
using System.Text;

namespace WcfServiceDemo
{
    // NOTE: You can use the "Rename" command on the "Refactor" menu to change the interface name "IService1" in both code and config file together.
    [ServiceContract]
    public interface IService
    {
        [OperationContract]
        CustomerData Get();

        [OperationContract]
        void Insert(string userName, string location);

        [OperationContract]
        void Update(int userId, string userName, string location);

        [OperationContract]
        void Delete(int userId);
    }
    [DataContract]
    public class CustomerData
    {
        public CustomerData()
        {
            this.CustomersTable = new DataTable("UserInformation");
        }

        [DataMember]
        public DataTable CustomersTable { get; set; }
    }
 }

write below code in service.cs

using System;
using System.Collections.Generic;
using System.Configuration;
using System.Data;
using System.Data.SqlClient;
using System.Linq;
using System.Runtime.Serialization;
using System.ServiceModel;
using System.Text;


namespace WcfServiceDemo
{
    // NOTE: You can use the "Rename" command on the "Refactor" menu to change the class name "Service1" in both code and config file together.
    public class Service : IService
    {
        public CustomerData Get()
        {
            string constr = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
            using (SqlConnection con = new SqlConnection(constr))
            {
                using (SqlCommand cmd = new SqlCommand("SELECT UserId, UserName, Location FROM MySampleDB"))
                {
                    using (SqlDataAdapter sda = new SqlDataAdapter())
                    {
                        cmd.Connection = con;
                        sda.SelectCommand = cmd;
                        using (DataTable dt = new DataTable())
                        {
                            CustomerData customers = new CustomerData();
                            sda.Fill(customers.CustomersTable);
                            return customers;
                        }
                    }
                }
            }
        }

        public void Insert(string userName, string location)
        {
            string constr = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
            using (SqlConnection con = new SqlConnection(constr))
            {
                using (SqlCommand cmd = new SqlCommand("INSERT INTO MySampleDB (UserName, Location) VALUES (@UserName, @Location)"))
                {
                    cmd.Parameters.AddWithValue("@UserName", userName);
                    cmd.Parameters.AddWithValue("@Location", location);
                    cmd.Connection = con;
                    con.Open();
                    cmd.ExecuteNonQuery();
                    con.Close();
                }
            }
        }

        public void Update(int userId, string userName, string location)
        {
            string constr = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
            using (SqlConnection con = new SqlConnection(constr))
            {
                using (SqlCommand cmd = new SqlCommand("UPDATE MySampleDB SET UserName = @UserName, Location = @Location WHERE UserId = @UserId"))
                {
                    cmd.Parameters.AddWithValue("@UserId", userId);
                    cmd.Parameters.AddWithValue("@UserName", userName);
                    cmd.Parameters.AddWithValue("@Location", location);
                    cmd.Connection = con;
                    con.Open();
                    cmd.ExecuteNonQuery();
                    con.Close();
                }
            }
        }

        public void Delete(int userId)
        {
            string constr = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
            using (SqlConnection con = new SqlConnection(constr))
            {
                using (SqlCommand cmd = new SqlCommand("DELETE FROM Customers WHERE UserId = @UserId"))
                {
                    cmd.Parameters.AddWithValue("@UserId", userId);
                    cmd.Connection = con;
                    con.Open();
                    cmd.ExecuteNonQuery();
                    con.Close();
                }
            }
        }
    }
}

IN CLIENT WRITE BELOW CODE

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Default.aspx.cs" Inherits="WcfClient.Default" %>

<!DOCTYPE html>

<html xmlns="http://www.w3.org/1999/xhtml">

<head runat="server">

    <title></title>

</head>

<body>

    <form id="form1" runat="server">

        <div>

            <asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="false" DataKeyNames="UserId"

                OnRowDataBound="OnRowDataBound" OnRowEditing="OnRowEditing" OnRowUpdating="OnRowUpdating"

                 OnRowDeleting="OnRowDeleting" EmptyDataText="No records has been added.">

                <Columns>

                    <asp:TemplateField HeaderText="Name" ItemStyle-Width="150">

                        <ItemTemplate>

                            <asp:Label ID="lblName" runat="server" Text='<%# Eval("UserName") %>'></asp:Label>

                        </ItemTemplate>

                        <EditItemTemplate>

                            <asp:TextBox ID="txtName" runat="server" Text='<%# Eval("UserName") %>'></asp:TextBox>

                        </EditItemTemplate>

                    </asp:TemplateField>

                    <asp:TemplateField HeaderText="Country" ItemStyle-Width="150">

                        <ItemTemplate>

                            <asp:Label ID="lblCountry" runat="server" Text='<%# Eval("Location") %>'></asp:Label>

                        </ItemTemplate>

                        <EditItemTemplate>

                            <asp:TextBox ID="txtCountry" runat="server" Text='<%# Eval("Location") %>'></asp:TextBox>

                        </EditItemTemplate>

                    </asp:TemplateField>

                    <asp:CommandField ButtonType="Link" ShowEditButton="true" ShowDeleteButton="true" ItemStyle-Width="150" />

                </Columns>

            </asp:GridView>

            <table border="1" cellpadding="0" cellspacing="0" style="border-collapse: collapse">

                <tr>

                    <td style="width: 150px">Name:<br />

                        <asp:TextBox ID="txtName" runat="server" Width="140" />

                    </td>

                    <td style="width: 150px">Country:<br />

                        <asp:TextBox ID="txtCountry" runat="server" Width="140" />

                    </td>

                    <td style="width: 100px">

                        <asp:Button ID="btnAdd" runat="server" Text="Add" OnClick="Insert" />

                    </td>

                </tr>

            </table>

        </div>

    </form>

</body>

</html>

in cs file write below code

using System;

using System.Collections.Generic;

using System.Linq;

using System.Web;

using System.Web.UI;

using System.Web.UI.WebControls;

namespace WcfClient

{

    public partial class Default : System.Web.UI.Page

    {

        protected void Page_Load(object sender, EventArgs e)

        {

            if (!this.IsPostBack)

            {

                this.BindGrid();

            }

        }

        private void BindGrid()

        {

            ServiceReference1.ServiceClient client = new ServiceReference1.ServiceClient();

            GridView1.DataSource = client.Get().CustomersTable;

            GridView1.DataBind();

        }

        protected void Insert(object sender, EventArgs e)

        {

            ServiceReference1.ServiceClient client = new ServiceReference1.ServiceClient();

            client.Insert(txtName.Text.Trim(), txtCountry.Text.Trim());

            this.BindGrid();

        }

        protected void OnRowEditing(object sender, GridViewEditEventArgs e)

        {

            GridView1.EditIndex = e.NewEditIndex;

            this.BindGrid();

        }

        protected void OnRowUpdating(object sender, GridViewUpdateEventArgs e)

        {

            GridViewRow row = GridView1.Rows[e.RowIndex];

            int customerId = Convert.ToInt32(GridView1.DataKeys[e.RowIndex].Values[0]);

            string name = (row.FindControl("txtName") as TextBox).Text;

            string country = (row.FindControl("txtCountry") as TextBox).Text;

            //CRUD_Service.ServiceCS service = new CRUD_Service.ServiceCS();

            ServiceReference1.ServiceClient client = new ServiceReference1.ServiceClient();

            client.Update(customerId, name, country);

            GridView1.EditIndex = -1;

            this.BindGrid();

        }

        protected void OnRowDeleting(object sender, GridViewDeleteEventArgs e)

        {

            int customerId = Convert.ToInt32(GridView1.DataKeys[e.RowIndex].Values[0]);

            //CRUD_Service.ServiceCS service = new CRUD_Service.ServiceCS();

            ServiceReference1.ServiceClient client = new ServiceReference1.ServiceClient();

            client.Delete(customerId);

            this.BindGrid();

        }

        protected void OnRowDataBound(object sender, GridViewRowEventArgs e)

        {

            if (e.Row.RowType == DataControlRowType.DataRow && e.Row.RowIndex != GridView1.EditIndex)

            {

                (e.Row.Cells[2].Controls[2] as LinkButton).Attributes["onclick"] = "return confirm('Do you want to delete this row?');";

            }

        }

    }

}