using System; namespace System.Data { public interface IDbCommand { string CommandText { get; set; } } public interface IDbDataAdapter { } } namespace System.Data.SqlClient { public class SqlCommand : IDbCommand { public SqlCommand(string commandText) { } string IDbCommand.CommandText { get; set; } } public class SqlDataAdapter : IDbDataAdapter { public SqlDataAdapter() { } public SqlDataAdapter(string sql) { } } } namespace MySql.Data.MySqlClient { using System.Data; public class MySqlCommand : IDbCommand { public MySqlCommand(string commandText) { } public string CommandText { get; set; } } public class MySqlHelper { public static object ExecuteScalar(string connectionString, string commandText) { return null; } } } namespace Microsoft.ApplicationBlocks.Data { class SqlHelper { public static object ExecuteScalar(string connectionString, string commandText) { return null; } } } namespace SqlClientTests { using System.Data; using System.Data.SqlClient; using MySql.Data.MySqlClient; using Microsoft.ApplicationBlocks.Data; class TestClass { public static void TestMethod(string text) { System.Data.IDbCommand command = new SqlCommand(text); command = new MySqlCommand(text); command.CommandText = text; new MySqlCommand(text).CommandText = text; new SqlDataAdapter(text); MySqlHelper.ExecuteScalar("", text); SqlHelper.ExecuteScalar("", text); } } }