dll工程的名字为NN，类的名字为TT

Option Explicit

Function test() As String

test = "test!!!!"

End Function

Public Function GetConn() As ADODB.Connection

Dim conn As ADODB.Connection

Set conn = New ADODB.Connection

Debug.Print ("ok")

Set GetConn = conn

End Function

exe工程的名字为NA,

Option Explicit

Private Sub Form_Load()

Dim a As NN.TT

Set a = New NN.TT

Dim b As Object

Set b = a.GetConn()

'这里的b就是一个adodb.connectioh对象

Debug.Print b.version()

End Sub