从C#dll使用ADODB连接到SQL Server

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Data.SqlClient;
using System.Runtime.InteropServices;

namespace Test
{

    [InterfaceType(ComInterfaceType.InterfaceIsDual),
    Guid("6E8B9F68-FB6C-422F-9619-3BA6D5C24E84")]
    public interface IConnection
    {
        bool Status { get; }
        bool Open();
    }

    [ClassInterface(ClassInterfaceType.None)]
    [Guid("B280EAA4-CE11-43AD-BACD-723783BB3CF2")]
    [ProgId("Test.Connection")]
    public class Connection : IConnection
    {
        private bool status;
        private SqlConnection conn;
        private string connString = "Data Source=[server]; Initial Catalog=[initial]; User ID=[username]; Password=[password]";

        public Connection()
        {
        }

        public bool Status
        {
            get
            {
                return status;
            }
        }

        public bool Open()
        {
            try
            {
                conn = new SqlConnection(connString);
                conn.Open();
                status = true;
                return true;
            }
            catch(Exception e)
            {
                e.ToString();
                return false;
            }
        }
    }
}

在添加对Excel的引用后,我可以使用简单的VBA代码测试连接,如下所示：

Sub TestConnection()

    Dim conn As Test.Connection
    Set conn = New Test.Connection

    Debug.Print conn.Status
    conn.Open
    Debug.Print conn.Status

End Sub

它输出：

False
True

所以一切都很好.现在,我想在我的C#库中创建自定义Recordset类,因此我决定使用ADODB库及其RecordSet而不是SqlDataReader,因为我打算使用一些大数据块.因此,我将代码修改为：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Data.SqlClient;
using System.Runtime.InteropServices;

namespace Test
{

    [InterfaceType(ComInterfaceType.InterfaceIsDual),
    Guid("6E8B9F68-FB6C-422F-9619-3BA6D5C24E84")]
    public interface IConnection
    {
        bool Status { get; }
        bool Open();
    }

    [ClassInterface(ClassInterfaceType.None)]
    [Guid("B280EAA4-CE11-43AD-BACD-723783BB3CF2")]
    [ProgId("Test.Connection")]
    public class Connection : IConnection
    {

        private bool status;
        private ADODB.Connection conn = new ADODB.Connection();
        private string connString = "Data Source=[server]; Initial Catalog=[initial]; User ID=[username]; Password=[password]";

        public Connection()
        {
        }

        public bool Status
        {
            get
            {
                return status;
            }
        }

        public bool Open()
        {
            try
            {
                conn.ConnectionString = connString;
                conn.Open();
                // conn.Open(connString, ["username"], ["password"], 0)
                // what else can I try? is this where it actually fails?
                status = true;
                return true;
            }
            catch (Exception e)
            {
                e.ToString();
                return false;
            }
        }

    }
}

我还添加了对Microsoft ActiveX数据对象6.1库的引用.

现在,当我执行VBA代码时,它输出：

0
0

但是我期望的值为0和1.在我看来,我好像没有正确连接到服务器(凭据与我刚刚从此代码中删除了实际数据一样).

我尝试使用连接字符串的不同变体,但是它总是返回0和0.我尝试使用新的GUID创建新项目,还尝试重命名项目,类等.没有任何效果.我怀疑它已建立连接,但不确定如何调试dll.

我已使用link1、link2、link3、link4作为参考

更新：
我已经按照TheKingDave的建议将异常写入了文件.这是异常错误消息

System.Runtime.InteropServices.COMException (0x80004005):
[Microsoft][ODBC Driver Manager] Data source name not found and no
default driver specified at ADODB._Connection.Open(String
ConnectionString, String UserID, String Password, Int32 Options) at
TestADODB.Connection.Open() in c:\Users\administrator\Documents\Visual
Studio 2012\Projects\Test\Test\Connection.cs:line 49

ADODB.Connection需要知道它连接到的数据库类型.