Executing dos command from VB.NET

Question

I need to execute an external process from VB.NET application, usually I run this process from command prompt:

c:\> net.exe use \\192.168.0.5\ipc$

When this command is executed, it displays a string like "The connection is successfull" OR "Access Denied" or any other relevant message.

I need to execute this command from vb.net and as well can I capture the output string?

Answer 1

Try below code, it will take your command as argument and print the output in the textbox.

Imports System.Diagnostics

Public Class frmConsoleDemo

Friend WithEvents txtConsoleOut As System.Windows.Forms.TextBox
Friend WithEvents txtConsoleIn As System.Windows.Forms.TextBox

Private psi As ProcessStartInfo
Private cmd As Process
Private Delegate Sub InvokeWithString(ByVal text As String)

Private Sub frmConsoleDemo_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load

    psi = New ProcessStartInfo("cmd.exe")

    Dim systemencoding As System.Text.Encoding = _
        System.Text.Encoding.GetEncoding(Globalization.CultureInfo.CurrentUICulture.TextInfo.OEMCodePage)

    With psi
        .UseShellExecute = False  ' Required for redirection
        .RedirectStandardError = True
        .RedirectStandardOutput = True
        .RedirectStandardInput = True
        .CreateNoWindow = True
        .StandardOutputEncoding = systemencoding  ' Use OEM encoding for console applications
        .StandardErrorEncoding = systemencoding
    End With

    ' EnableraisingEvents is required for Exited event
    cmd = New Process With {.StartInfo = psi, .EnableRaisingEvents = True}

    AddHandler cmd.ErrorDataReceived, AddressOf Async_Data_Received
    AddHandler cmd.OutputDataReceived, AddressOf Async_Data_Received
    AddHandler cmd.Exited, AddressOf CMD_Exited

    cmd.Start()
    ' Start async reading of the redirected streams
    ' Without these calls the events won't fire
    cmd.BeginOutputReadLine()
    cmd.BeginErrorReadLine()

    Me.txtConsoleIn.Select()
End Sub

Private Sub CMD_Exited(ByVal sender As Object, ByVal e As EventArgs)
    Me.Close()
End Sub

' This sub gets called in a different thread so invokation is required
Private Sub Async_Data_Received(ByVal sender As Object, ByVal e As DataReceivedEventArgs)
    Me.Invoke(New InvokeWithString(AddressOf Sync_Output), e.Data)
End Sub

Private Sub Sync_Output(ByVal text As String)
    txtConsoleOut.AppendText(text & Environment.NewLine)
    txtConsoleOut.ScrollToCaret()
End Sub

' Sending console commands here
Private Sub txtConsoleIn_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles txtConsoleIn.KeyPress
    If e.KeyChar = ControlChars.Cr Then
        cmd.StandardInput.WriteLine(txtConsoleIn.Text)
        txtConsoleIn.Clear()
    End If
End Sub

' Two text boxes called txtConsoleOut and txtConsoleIn
Public Sub New()
    Me.txtConsoleOut = New System.Windows.Forms.TextBox()
    Me.txtConsoleIn = New System.Windows.Forms.TextBox()
    Me.SuspendLayout()
    '
    'txtConsoleOut
    '
    Me.txtConsoleOut.Anchor = CType((((System.Windows.Forms.AnchorStyles.Top Or System.Windows.Forms.AnchorStyles.Bottom) _
                Or System.Windows.Forms.AnchorStyles.Left) _
                Or System.Windows.Forms.AnchorStyles.Right), System.Windows.Forms.AnchorStyles)
    Me.txtConsoleOut.Location = New System.Drawing.Point(12, 12)
    Me.txtConsoleOut.Multiline = True
    Me.txtConsoleOut.Name = "txtConsoleOut"
    Me.txtConsoleOut.ReadOnly = True
    Me.txtConsoleOut.ScrollBars = System.Windows.Forms.ScrollBars.Both
    Me.txtConsoleOut.Size = New System.Drawing.Size(665, 494)
    Me.txtConsoleOut.TabIndex = 0
    '
    'txtConsoleIn
    '
    Me.txtConsoleIn.Anchor = CType(((System.Windows.Forms.AnchorStyles.Bottom Or System.Windows.Forms.AnchorStyles.Left) _
                Or System.Windows.Forms.AnchorStyles.Right), System.Windows.Forms.AnchorStyles)
    Me.txtConsoleIn.Location = New System.Drawing.Point(10, 512)
    Me.txtConsoleIn.Name = "txtConsoleIn"
    Me.txtConsoleIn.Size = New System.Drawing.Size(667, 20)
    Me.txtConsoleIn.TabIndex = 1
    '
    'frmConsoleDemo
    '
    Me.AutoScaleDimensions = New System.Drawing.SizeF(6.0!, 13.0!)
    Me.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font
    Me.ClientSize = New System.Drawing.Size(689, 544)
    Me.Controls.Add(Me.txtConsoleIn)
    Me.Controls.Add(Me.txtConsoleOut)
    Me.Name = "frmConsoleDemo"
    Me.Text = "Console redirect demo"
    Me.ResumeLayout(False)
    Me.PerformLayout()

End Sub

End Class

Hope it helps..