主题：无法在 DLL“ClassLibrary2.dll”中找到名为“autha”的入口点。

这是DLL的语句

Public Class Class1
    Public Function autha(ByVal rc As String) As String
        Dim es As New ServiceReference1.authRequest
        Dim sd As New ServiceReference1.authRequestBody
        sd.access = rc
        es.Body = sd
        Dim web As ServiceReference1.Hoslink
        Dim cc As String = web.auth(es).ToString
        Return cc

    End Function
End Class

全局代码

Public Declare Function Auth Lib "ClassLibrary2.dll" Alias "autha" (ByVal rc As String) As String

然后直接添加引用即可：http://www.foxtable.com/webhelp/topics/1936.htm，注意vs的发布的dll必须是.net framework 4.0的

dim a as new dll的命名空间.Class1

解决了，感谢蓝老师