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How to read Console buffer in VBNET?


I've seen a C# example using ConsoleRead API function but when I've tried to translate it to VBNET I get a lots of errors, also in other sites like pinvoke the unique example is for C# too, I can't find any good information for VBNET of ConsoleRead API function (if exist a way to read the console buffer without APIS then I get no idea).

Also I've tried this console buffer reader Class for VBNET (http://pastebin.com/XYxakDTV) but it throws an unhandled exception with message like this "Controller not valid".

Someone could illustrate me and all other people with an example for VBNET of how to launch a process from a GUI app (WindowsForm) to read the console output to retrieve characters/strings?

UPDATE:

I'm not sure but I think that a launched process (using System.Process Class) does not assign the console to the app so I think that all the examples seen here in MSDN could not help me: http://msdn.microsoft.com/en-us/library/system.console.aspx


Solution

  • Use

    StandardOutput.Read
    

    I think that the answer is the same as for your other question Run a commandline process and get the output while that process still running?

    Edit you are asking for an form application to read console output. So let's have a console application ():

    Module Module1
    
        Sub Main()
            While True
                ' data = Console.ReadKey.KeyChar
                Dim Generator As System.Random = New System.Random()
                Console.Write(Generator.Next(0, 100) & " ")
                Threading.Thread.Sleep(1000)
            End While
        End Sub
    
    End Module 
    

    It generates a space separated numbers one per second. Now the forms application. Let's have a form with a multiline TextBox named txtResult and a button cmdStart :

    Private Sub cmdStart_Click(sender As Object, e As EventArgs) Handles cmdStart.Click
            Dim ProcInfo As New ProcessStartInfo With
                {.FileName = "DataApp.exe", .RedirectStandardOutput = True, .UseShellExecute = False}
            Dim proc As Process = Process.Start(ProcInfo)
    
            While Not proc.HasExited
                Dim a As String = ChrW(proc.StandardOutput.Read)
                If a = " " Then
                    txtResult.Text &= vbCrLf
                Else
                    txtResult.Text &= a
                End If
                Threading.Thread.Sleep(100)
                Application.DoEvents()
            End While
    
        End Sub
    

    It writes the numbers to the TextBox one per a line. There is no API magic but it works.