how can we run a dos command from VB

[softweng]

This works well for me. It allows you to wait until the process finishes.
Put this code in a Module (Module1.bas):

option Explicit
    
'//public Constants
public Const NORMAL_PRIORITY_CLASS = &H20&
public Const INFINITE = -1&
    
'//public Types
public Type STARTUPINFO
   cb as Long
   lpReserved as string
   lpDesktop as string
   lpTitle as string
   dwX as Long
   dwY as Long
   dwXSize as Long
   dwYSize as Long
   dwXCountChars as Long
   dwYCountChars as Long
   dwFillAttribute as Long
   dwFlags as Long
   wShowWindow as Integer
   cbReserved2 as Integer
   lpReserved2 as Long
   hStdInput as Long
   hStdOutput as Long
   hStdError as Long
End Type
    
public Type PROCESS_INFORMATION
   hProcess as Long
   hThread as Long
   dwProcessID as Long
   dwThreadID as Long
End Type
    
'//API Declarations
public Declare Function WaitForSingleObject Lib "kernel32" (byval _
   hHandle as Long, byval dwMilliseconds as Long) as Long
    
public Declare Function CreateProcessA Lib "kernel32" (byval _
   lpApplicationName as Long, byval lpCommandLine as string, byval _
   lpProcessAttributes as Long, byval lpThreadAttributes as Long, _
   byval bInheritHandles as Long, byval dwCreationFlags as Long, _
   byval lpEnvironment as Long, byval lpCurrentDirectory as Long, _
   lpStartupInfo as STARTUPINFO, lpProcessInformation as _
   PROCESS_INFORMATION) as Long
    
public Declare Function CloseHandle Lib "kernel32" (byval _
   hObject as Long) as Long



    
Put This Code In A Form (Form1):

private Sub Command1_Click()
    Dim AppToRun as string
    Dim ParamForApp as string
    Dim CmdLine as string
       
    '//set Application to Run
    AppToRun = "C:\WINNT\System32\CMD.exe"
       
    '//set Command Line Parameters
    '//The "/C" Tells Windows to Run The Command then Terminate
    '//The Command Line (CMD.exe)
    ParamForApp = " /C MD New_Folder" '//Make new Directory Called 'New_Folder'
       
    '//Build Command string
    CmdLine = AppToRun & ParamForApp
       
    '//Shell App And Wait for It to Finish
    ExecCmd CmdLine
           
End Sub
    
public Sub ExecCmd(CmdLine as string)
    Dim Proc as PROCESS_INFORMATION
    Dim start as STARTUPINFO
    Dim ReturnValue as Integer
       
    '//Initialize The STARTUPINFO Structure
    start.cb = len(start)
       
    '//Start The Shelled Application
    ReturnValue = CreateProcessA(0&, CmdLine, 0&, 0&, 1&, _
       NORMAL_PRIORITY_CLASS, 0&, 0&, start, Proc)
       
    '//Wait for The Shelled Application to Finish
    Do
       ReturnValue = WaitForSingleObject(Proc.hProcess, 0)
       DoEvents
    Loop Until ReturnValue <> 258
       
    '//Close Handle to Shelled Application
    ReturnValue = CloseHandle(Proc.hProcess)
       
End Sub

Kris
Software Engineer
Phoenix,AZ