Web Development

<WebMethod()> _
Public Function HelloWorld() As String
    Return "Hello World"
End Function

[WebMethod()]
public string HelloWorld()
{
    return "Hello World";
}

public class Service1 : System.Web.Services.WebService
    {
        public DataSet UserDataset = new DataSet();
        public SqlDataAdapter UserAdapter = new SqlDataAdapter("Select Query",new SqlConnection("connection string"));

        [WebMethod]
        public string HelloWorld()
        {
            return "Hello World";
        }

        [WebMethod]
        public DataSet GetUserData()
        {
            UserAdapter.Fill(UserDataset);
            return UserDataset;
        }

        [WebMethod]
        public DataSet UpdateUserData(DataSet ds)
        {
            if(ds != null)
            {
                UserAdapter.Update(ds);
                return ds;
            }
            else
            {
                return null;
            }
        }

        private void InitializeComponent()
        {
            this.UserDataset = new System.Data.DataSet();
            ((System.ComponentModel.ISupportInitialize)(this.UserDataset)).BeginInit();
            // 
            // UserDataset
            // 
            this.UserDataset.DataSetName = "NewDataSet";
            ((System.ComponentModel.ISupportInitialize)(this.UserDataset)).EndInit();

        }
    }

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Web.Services;
using System.Configuration.Assemblies;
using System.Xml;


namespace UserWindow
{
    public partial class UserWindow : Form
    {
        public UserWindow()
        {
            InitializeComponent();
        }

        private void LoadData_Click(object sender, EventArgs e)
        {
            DataSet ds = new DataSet();
            ds = UserWebService1.Service1.(Here I am getting Reference, GenerateXMLMappings and EqualReference methods)
        }
    }
}

private void LoadData_Click(object sender, EventArgs e)
{
    DataSet ds = new DataSet();
    UserWebService1.Service1 WebSrvc = new UserWebService1.Service1();
    ds = WebSrvc.YouFunctionHere;
}