如何在VB .Net中使用Web客户端

Question

Greatings，我有一段代码，我在VB中执行代码时遇到错误。错误说“'Captcha'没有被宣布。” 。 Enyone？## Heading ##

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代码：

With New Net.WebClient
    Try
        Dim b() As Byte = .UploadFile(New System.Uri("127.0.0.1"), Captcha.Path)
        Captcha.Solution = System.Text.Encoding.ASCII.GetString(b).Split(CChar("|"))(5).ToString
    Catch ex As Exception
        Result.FailMessage = "Could not retrieve captcha response; " & ex.Message
        Exit Try
    End Try
End With

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