c# - 在处理 SQLConnection 之前，我是否必须 Close() ？

Question

根据我的其他 question here about Disposable objects ，我们应该在 using block 结束之前调用 Close() 吗？

using (SqlConnection connection = new SqlConnection())
using (SqlCommand command = new SqlCommand())
{
    command.CommandText = "INSERT INTO YourMom (Amount) VALUES (1)";
    command.CommandType = System.Data.CommandType.Text;

    connection.Open();
    command.ExecuteNonQuery();

    // Is this call necessary?
    connection.Close();
}

Answer 1

由于您有一个 using block ，因此将调用 SQLCommand 的 Dispose 方法并关闭连接:

// System.Data.SqlClient.SqlConnection.Dispose disassemble
protected override void Dispose(bool disposing)
{
    if (disposing)
    {
        this._userConnectionOptions = null;
        this._poolGroup = null;
        this.Close();
    }
    this.DisposeMe(disposing);
    base.Dispose(disposing);
}