Asp.net : Classe Conexão

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data.SqlClient;
using System.Configuration;

namespace teste
{
    public class Conexao : IDisposable
    {
        private SqlConnection Connection;

        public Conexao()
        {
            var connectionString = "Server=localhost\\ALAN;Database=ex22;User ID=sa;         Password=sqlsdk8;";

            Connection = new SqlConnection(connectionString);
        }

        public SqlDataReader Consulta(string query)
        {

            var command = new SqlCommand(query, Connection);
           
            Connection.Open();

            return command.ExecuteReader();
        }

        public void Insert(string query)
        {
            var command = new SqlCommand(query, Connection);

            Connection.Open();

            command.ExecuteNonQuery();
        }

        public void Dispose()
        {
            Connection.Close();
        }
    }
}

Consulta Example

Conexao conexao = new Conexao();
string query = "select nome from cliente where idcliente=23";
var datareader = conexao.Consulta(query);
string texto = null;
if (datareader.Read()) { texto = Convert.ToString(datareader["nome"]); }
conexao.Dispose();
txtTeste.Text = texto;

Insert Example

query = "insert into cliente (nome,cpf,cartao) values('alan',7890,76899)";
conexao.Insert(query);
conexao.Dispose();