很多人都在问如何用VB读取CMD命令执行后的回显,这个问题用VB做确实麻烦···
这个代码是通过PIPE管道读取回显,保存为类调用即可。
类模块代码如下:
Option Explicit
'The CreatePipe function creates an anonymous pipe,
'and returns handles to the read and write ends of the pipe.
Private Declare Function CreatePipe Lib "kernel32" ( _
phReadPipe As Long, _
phWritePipe As Long, _
lpPipeAttributes As Any, _
ByVal nSize As Long) As Long
'Used to read the the pipe filled by the process create
'with the CretaProcessA function
Private Declare Function ReadFile Lib "kernel32" ( _
ByVal hFile As Long, _
ByVal lpBuffer As String, _
ByVal nNumberOfBytesToRead As Long, _
lpNumberOfBytesRead As Long, _
ByVal lpOverlapped As Any) As Long
'Structure used by the CreateProcessA function
Private Type SECURITY_ATTRIBUTES
nLength As Long
lpSecurityDescriptor As Long
bInheritHandle As Long
End Type
'Structure used by the CreateProcessA function
Private Type STARTUPINFO
cb As Long
lpReserved As Long
lpDesktop As Long
lpTitle As Long
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
'Structure used by the CreateProcessA function
Private Type PROCESS_INFORMATION
hProcess As Long
hThread As Long
dwProcessID As Long
dwThreadID As Long
End Type
'This function launch the the commend and return the relative process
'into the PRECESS_INFORMATION structure
Private Declare Function CreateProcessA Lib "kernel32" ( _
ByVal lpApplicationName As Long, _
ByVal lpCommandLine As String, _
lpProcessAttributes As SECURITY_ATTRIBUTES, _
lpThreadAttributes As SECURITY_ATTRIBUTES, _
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
'Close opened handle
Private Declare Function CloseHandle Lib "kernel32" ( _
ByVal hHandle As Long) As Long
'Consts for the above functions
Private Const NORMAL_PRIORITY_CLASS = &H20&
Private Const STARTF_USESTDHANDLES = &H100&
Private Const STARTF_USESHOWWINDOW = &H1
Private mCommand As String 'Private variable for the CommandLine property
Private mOutputs As String 'Private variable for the ReadOnly Outputs property
'Event that notify the temporary buffer to the object
Public Event ReceiveOutputs(CommandOutputs As String)
'This property set and get the DOS command line
'It's possible to set this property directly from the
'parameter of the ExecuteCommand method
Public Property Let CommandLine(DOSCommand As String)
mCommand = DOSCommand
End Property
Public Property Get CommandLine() As String
CommandLine = mCommand
End Property
'This property ReadOnly get the complete output after
'a command execution
Public Property Get Outputs()
Outputs = mOutputs
End Property
Public Function ExecuteCommand(Optional CommandLine As String) As String
Dim proc As PROCESS_INFORMATION 'Process info filled by CreateProcessA
Dim ret As Long 'long variable for get the return value of the
'API functions
Dim start As STARTUPINFO 'StartUp Info passed to the CreateProceeeA
'function
Dim sa As SECURITY_ATTRIBUTES 'Security Attributes passeed to the
'CreateProcessA function
Dim hReadPipe As Long 'Read Pipe handle created by CreatePipe
Dim hWritePipe As Long 'Write Pite handle created by CreatePipe
Dim lngBytesread As Long 'Amount of byte read from the Read Pipe handle
Dim strBuff As String * 256 'String buffer reading the Pipe
'if the parameter is not empty update the CommandLine property
If Len(CommandLine) > 0 Then
mCommand = CommandLine
End If
'if the command line is empty then exit whit a error message
If Len(mCommand) = 0 Then
MsgBox "Command Line empty", vbCritical
Exit Function
End If
'Create the Pipe
sa.nLength = Len(sa)
sa.bInheritHandle = 1&
sa.lpSecurityDescriptor = 0&
ret = CreatePipe(hReadPipe, hWritePipe, sa, 0)
If ret = 0 Then
'If an error occur during the Pipe creation exit
MsgBox "CreatePipe failed. Error: " & Err.LastDllError, vbCritical
Exit Function
End If
'Launch the command line application
start.cb = Len(start)
start.dwFlags = STARTF_USESTDHANDLES Or STARTF_USESHOWWINDOW
'set the StdOutput and the StdError output to the same Write Pipe handle
start.hStdOutput = hWritePipe
start.hStdError = hWritePipe
'Execute the command
ret& = CreateProcessA(0&, mCommand, sa, sa, 1&, _
NORMAL_PRIORITY_CLASS, 0&, 0&, start, proc)
If ret <> 1 Then
'if the command is not found ....
MsgBox "File or command not found", vbCritical
Exit Function
End If
'Now We can ... must close the hWritePipe
ret = CloseHandle(hWritePipe)
mOutputs = ""
'Read the ReadPipe handle
Do
ret = ReadFile(hReadPipe, strBuff, 256, lngBytesread, 0&)
mOutputs = mOutputs & Left(strBuff, lngBytesread)
'Send data to the object via ReceiveOutputs event
RaiseEvent ReceiveOutputs(Left(strBuff, lngBytesread))
Loop While ret <> 0
'Close the opened handles
ret = CloseHandle(proc.hProcess)
ret = CloseHandle(proc.hThread)
ret = CloseHandle(hReadPipe)
'Return the Outputs property with the entire DOS output
ExecuteCommand = mOutputs
End Function
-----------------------------------------------------------------------------------------------------------------------------------
调用代码:
Private WithEvents objDOS As DOSOutputs '定义为全局变量
objDOS.CommandLine = "net user"
objDOS.ExecuteCommand '执行net user命令
Private Sub objDOS_ReceiveOutputs(CommandOutputs As String) '输入结果
txtOutputs.Text = txtOutputs.Text & CommandOutputs
End Sub
程序运行截图:
Private Sub Form_Load()
Set objdos = New dosoutputs
End Sub
Private Sub Command1_Click()
'objdos.commandline = "netstat -an"
objdos.commandline = txtcmd.Text
objdos.ExecuteCommand '执行net user命令
End Sub