如果InnerException为null,则不显示

您可能应该在外部范围中声明您的变量,还应该检查Nothing而不是空消息字符串。

Dim ErrorDetails As String
Dim err As System.Exception = Server.GetLastError

If err.InnerException Is Nothing Then

  ErrorDetails = err.Message

Else

  ErrorDetails = err.InnerException.Message

End If

这将获得最内部的异常消息

while err is not nothing
    ErrorDetails = err.message
    err = err.innerexception
end while

编辑-

让它看起来像这样:

Dim err As System.Exception = Server.GetLastError
Dim ErrorDetails As String

    while err is not nothing
        ErrorDetails = err.message
        err = err.innerexception
    end while

err.InnerException.Message 将引发异常。你需要

If Not err.InnerException Is Nothing

Dim ErrorDetails As List(Of String) = New List(Of String)
Dim err As Exception = Server.GetLastError

While Not err Is Nothing
  ErrorDetails.Add(err.Message)
  err = err.InnerException
End While