批量编程,错误处理和启动命令

Question

我刚开始学习如何编写脚本.我试图了解系统如何处理错误级别以及如何在错误处理中使用它们.我知道环境变量%ERRORLEVEL%与系统的错误级别之间存在差异.如果我理解正确,那么 If ERRORLEVEL 1 代码将在检查上一个命令的错误级别之前检查环境变量.

所以,在我的程序中,我试图连接一个启动/停止脚本,它将启动/停止给定机器的所有脚本(用于测试我只是使用一个应用程序notepad.exe作为示例).我有两个包装脚本,可以通过将参数传递给独立脚本来启动或停止应用程序.如果独立脚本中存在错误,它将使用以下命令设置errorlevel EXIT /B n

命令.一旦控制返回到调用脚本,如果退出状态为非零,它将转到错误处理脚本.

首先,我手动将%ERRORLEVEL%设置为零,然后在START或TASKKILL命令后测试错误.但后来我读到清除%ERRORLEVEL% SET ERRORLEVEL= 是一个更好的方法.当我尝试启动应用程序时,我的问题就出现了

START "" notepad.exe

每当我在此命令之后测试errorlevel时,它总是大于或等于1,除非我在运行start命令之前使用SET ERRORLEVEL = 0.我已经为下面的四个脚本插入了代码.任何见解和建议将不胜感激.

appstart.bat:

@echo off
:: Script for application Start
set ERRORLEVEL=
:: ****
:: Additional Batch files will be executed from within this file
:: Example: 
::     Call Appbat01.bat
:: The called batch file should set ERRORLEVEL non-zero if error
:: ****

call test.bat -start
if ERRORLEVEL 1 (call error.bat) 
echo.
echo Control was returned to appstart.bat...
:: **** End Calls
goto end

:end

appstop.bat:

@echo off
:: Script for application Start
set ERRORLEVEL=
:: ****
:: Additional Batch files will be executed from within this file
:: Example: 
::     Call Appbat01.ba
:: The called batch file should set ERRORLEVEL non-zero if error
:: ****

call test.bat -stop
if ERRORLEVEL 1 (call error.bat) 
echo.
echo Control was returned to appstop.bat...
:: **** End Calls
goto end

:end

test.bat的:

@echo off
if "%1"=="-start" goto :start
if "%1"=="-stop" goto :stop
goto wrongParams

:start
::****
:: Insert start up stripts here...
:: If there is an error, set ERRORLEVEL=1
::****
    set ERRORLEVEL=0
    echo.
    echo ********
    echo starting the service...
    echo.
    ::start "" "C:\Program Files\Microsoft Office\office11\winword.exe"
    start notepad.exe
    if ERRORLEVEL 1 goto error
    qprocess notepad.exe
    echo *Start.success* ERRORLEVEL is: %ERRORLEVEL%
    echo.
    goto end

:stop
::****
:: Insert stopping stripts here...
:: If there is an error, set ERRORLEVEL>1
::****
    set ERRORLEVEL=0
    echo.
    echo ********
    echo stopping the service...
    echo.
    qprocess notepad.exe 
    taskkill /f /im notepad.exe
    if ERRORLEVEL 1 goto noProcess
    goto end

:noProcess
    set ERRORLEVEL=2
    echo *noProcess* ERRORLEVEL is now: %ERRORLEVEL%
    echo.
    exit /b 2
:error
:: Errorhandler. Log application status and cause of error here. Set
:: ERRORLEVEL > 1 before returning to caller. 
    set ERRORLEVEL=1
    echo.
    echo **** Error handler inside test.bat ****
    echo.
    echo *error* ERRORLEVEL is now: %ERRORLEVEL%
    echo.
    exit /b 1

:wrongParams
:: Output an error if the wrong parameters were passed to this script.
:: Maybe try to self correct the parameter...
    set ERRORLEVEL=1
    echo.
    echo '%1' is an invalid parameter.
    echo Usage: %0 [-stop ^| -start] 
    echo *wrongParams* ERRORLEVEL is now: %ERRORLEVEL%
    echo.
    exit /b 1
:end

error.bat:

@echo off
echo **** You have reached error.bat ****
echo ERRORLEVEL inside of error.bat is: %ERRORLEVEL%
echo.
::*** Handle error...***
goto error%ERRORLEVEL%

:error2
    echo The process could not be stopped for some reason.
    goto end
:error1
    echo The process had an error in start up.
::***                ***
    goto end

:end

Answer 1

你永远不应该设置%errorlevel%变量.你是对的,存在差异; 从现有进程获得的错误级别是一个内部寄存器,您可以使用%errorlevel%语法读取该错误级别.但是,如果创建名为ERRORLEVEL的变量,它将屏蔽内部寄存器,并且您将无法访问退出代码.

如果需要将errorlevel寄存器设置为特定值,可以使用以下命令执行此操作:

%comspec% /c exit %value%

这将生成一个立即退出所需代码的进程.