how to add the service in client application.

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

namespace Employee
{
    // NOTE: If you change the interface name "IService1" here, you must also update the reference to "IService1" in App.config.
    [ServiceContract]
    public interface IService1
    {
        [OperationContract]
        DataSet GetEmployeerid();

        [OperationContract]
        List<CompositeType> GetDataUsingDataContract(CompositeType composite);

        // TODO: Add your service operations here
    }

    // Use a data contract as illustrated in the sample below to add composite types to service operations
    [DataContract]
    public class CompositeType
    {
          int   empid;
         string ename;
         string address;
         string city ;
         string state ;
         string employeerid;

        [DataMember]
         public int Empid
        {
            get { return empid; }
            set { empid = value; }
        }

        [DataMember]
        public string Ename
        {
            get { return ename; }
            set { ename = value; }
        }
        [DataMember]
        public string Address
        {
            get { return address; }
            set { address = value; }
        }
        [DataMember]
        public string City
        {
            get { return city; }
            set { city = value; }
        }
        [DataMember]
        public string State
        {
            get { return state; }
            set { state = value; }
        }
        [DataMember]
        public string Employeerid
        {
            get { return employeerid; }
            set { employeerid = value; }
        }
    }
}

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

namespace Employee
{
    // NOTE: If you change the class name "Service1" here, you must also update the reference to "Service1" in App.config.
    public class Service1 : IService1
    {
        public  DataSet GetEmployeerid()
        {
            String strConnection = ConfigurationManager.ConnectionStrings["MyConsString"].ConnectionString;
            SqlConnection conn = new SqlConnection(strConnection);
            SqlCommand cmd = new SqlCommand("select * from Employeertable where Employeerid=@Employeerid ", conn);
             conn.Open();
            SqlDataAdapter da=new SqlDataAdapter(cmd);            
             DataSet ds = new DataSet ();
             da.Fill(ds);
             return ds;
    
        }

        public List<compositetype> GetDataUsingDataContract(CompositeType composite)
        {
            List<compositetype> CompositeType = new List<compositetype>();

            {
                String strConnection = ConfigurationManager.ConnectionStrings["MyConsString"].ConnectionString;
                SqlConnection conn = new SqlConnection(strConnection);
                SqlCommand cmd = new SqlCommand("select * from Employeetable ", conn);
                conn.Open();
                SqlDataAdapter da = new SqlDataAdapter(cmd);
                DataTable dt = new DataTable();
                da.Fill(dt);
                if (dt.Rows.Count > 0)
                {
                    for (int i = 0; i < dt.Rows.Count; i++)
                    {
                        CompositeType obj = new CompositeType();
                        obj.Empid = Convert.ToInt32(dt.Rows[i]["Empid"].ToString());
                        obj.Ename = dt.Rows[i]["Ename"].ToString();
                        obj.Address = dt.Rows[i]["Address"].ToString();
                        obj.City = dt.Rows[i]["City"].ToString();
                        obj.State = dt.Rows[i]["State"].ToString();
                        obj.Employeerid = dt.Rows[i]["Employeerid"].ToString();
                        CompositeType.Add(obj);
                    }
                }
                conn.Close();
            }
            return CompositeType;
        }

        }
    }

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

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title>Untitled Page</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
&nbsp;<asp:Label ID="Label1" runat="server" Text="Employeerid">
    </asp:Label>&nbsp;&nbsp;
        <asp:DropDownList ID="DropDownList1" runat="server" Height="20px" Width="192px">
         <asp:ListItem>...Select...</asp:ListItem>
            <asp:ListItem>TCD</asp:ListItem>
            <asp:ListItem>Hmsa</asp:ListItem>
             <asp:ListItem>Dell</asp:ListItem>
        </asp:DropDownList>
&nbsp;
        <asp:Button ID="Button1" runat="server" Text="Search"  />
        <br />
        <br />
        <asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False">
            <Columns>

                <asp:BoundField DataField="Empid" HeaderText="Empid" />
                <asp:BoundField DataField="Ename" HeaderText="Ename" />
                <asp:BoundField DataField="Address" HeaderText="Address" />
                <asp:BoundField DataField="City" HeaderText="City" />
                <asp:BoundField DataField="State" HeaderText="State" />
                <asp:BoundField DataField="Employeerid" HeaderText="Employeerid" />
            </Columns>
        </asp:GridView>

    </div>
    </form>
</body>
</html>