How To Consume Web Service

<%@ WebService Language="C#" Class="GetInfo" %>

using System;
using System.Data;
using System.Data.SqlClient;
using System.Web.Services;

[WebService(Description="My Suppliers List Web Service")]

public class GetInfo : WebService {

[WebMethod(BufferResponse=true)]

    public DataSet ShowSuppliers (string str) {

// Your Code Here, This is Sample Code
    SqlConnection dbConnection = new SqlConnection("server=(local);uid=sa;pwd=;database=Northwind;");

    SqlDataAdapter objCommand = new SqlDataAdapter("select ContactName, CompanyName, City, Phone from Suppliers where Country = '" + str + "' order by ContactName asc", dbConnection);

    DataSet DS = new DataSet();

    objCommand.Fill(DS);

    return DS;

    dbConnection.Close();
    dbConnection = null;

    }

}