关于Hide Run CMD

Question

我想在vb.net下运行cmd hide，代码为打击：

Dim oProcess1 As New Process()
    Dim oStartInfo1 As New ProcessStartInfo()
    oStartInfo1.Verb = "runas"
    oStartInfo1.FileName = "cmd.exe"
    oStartInfo1.Arguments = " /c exit /b " & szCode & " | echo %=exitcode% "
    'oStartInfo1.CreateNoWindow = True
    'oStartInfo1.WindowStyle = ProcessWindowStyle.Hidden
    oStartInfo1.UseShellExecute = False
    oStartInfo1.RedirectStandardOutput = True
    oProcess1.StartInfo = oStartInfo1
    oProcess1.Start()
    Dim sOutput1 As String
    Using oStreamReader As System.IO.StreamReader = oProcess1.StandardOutput
        sOutput1 = oStreamReader.ReadToEnd()
    End Using

但是当我在CMD下运行时，输出字符串是：%=exitcode%：

cmd /c exit /b 1074065420  | echo %=exitcode%

输出为：4004F00C 如何在vb.net下获得正确的结果？