c# - SqlConnection.Close() 在 using 语句中

Question

我正在使用这段代码:

    public void InsertMember(Member member)
    {
        string INSERT = "INSERT INTO Members (Name, Surname, EntryDate) VALUES (@Name, @Surname, @EntryDate)";

        using (sqlConnection = new SqlConnection(sqlConnectionString_WORK))
        {
            sqlConnection.Open();

            using (SqlCommand sqlCommand = new SqlCommand(INSERT, sqlConnection))
            {
                sqlCommand.Parameters.Add("@Name", SqlDbType.VarChar).Value = member.Name;
                sqlCommand.Parameters.Add("@Surname", SqlDbType.VarChar).Value = member.Surname;
                sqlCommand.Parameters.Add("@EntryDate", SqlDbType.Date).Value = member.EntryDate;

                sqlCommand.ExecuteNonQuery();
            }
        }
    }

在处理之前不加sqlConnection.Close();是不是错了？我是说。它没有显示任何错误，根本没有问题。最好先关闭它吗？如果是，为什么？

Answer 1

无需Close or Dispose using block 将为您处理。

如 MSDN 所述:

The following example creates a SqlConnection, opens it, displays some of its properties. The connection is automatically closed at the end of the using block.

private static void OpenSqlConnection(string connectionString) 
{
    using (SqlConnection connection = new SqlConnection(connectionString))
    {
        connection.Open();
        Console.WriteLine("ServerVersion: {0}", connection.ServerVersion);
        Console.WriteLine("State: {0}", connection.State);
    } 
}