是否有可能在VB6中生成同步进程(即调用外部.exe),等待它终止,并获取返回值?
我们有遗留代码(显然在VB6中)我们需要调用.NET应用程序来执行一些复杂的任务,并且基于.NET应用程序的返回值,要么继续要么失败.有没有更好的方法来做这样的事情?
你的第一个选择可能是暴露一个接口,将.NET接口暴露给COM并使用它(它更清洁),但如果由于某种原因你必须通过一个衍生过程来完成它使用这个VB6代码.
Private 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 Private Type PROCESS_INFORMATION hProcess As Long hThread As Long dwProcessID As Long dwThreadID As Long End Type Private Declare Function WaitForSingleObject Lib "kernel32" (ByVal hHandle As Long, ByVal dwMilliseconds As Long) As Long Private 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 Private Declare Function CloseHandle Lib "kernel32" (ByVal hObject As Long) As Long Private Declare Function GetExitCodeProcess Lib "kernel32" (ByVal hProcess As Long, lpExitCode As Long) As Long Private Const NORMAL_PRIORITY_CLASS = &H20& Private Const INFINITE = -1& Private Const SW_HIDE = 0 Private Const SW_SHOWMINNOACTIVE = 7 Public Function ExecCmd(cmdline As String, workdir As String) As Integer Dim proc As PROCESS_INFORMATION Dim start As STARTUPINFO Dim ret as Long ChDrive Left(workdir, 1) & ":" ChDir workdir start.cb = Len(start) start.wShowWindow = SW_SHOWMINNOACTIVE Call CreateProcessA(0&, cmdline, 0&, 0&, 1&, NORMAL_PRIORITY_CLASS, 0&, 0&, start, proc) Call WaitForSingleObject(proc.hProcess, INFINITE) Call GetExitCodeProcess(proc.hProcess, ret) Call CloseHandle(proc.hThread) Call CloseHandle(proc.hProcess) ExecCmd=ret End Function