批次变量不能

Question

我有以下批处理脚本：

@echo off 
color 2f 
title "USERS MANAGEMENT IN A LAN" 
:top 
echo *************************************************************** 
echo. 
echo SELECT ACTIONS 
echo. 
echo *************************************************************** 
echo. 
echo [1] Ping the service     Params: unu 
echo [2] TBD 
echo. 
echo [e] Exit 
echo. 
echo *************************************************************** 
echo Enter the number of the website which you would like to go to: 
echo. 
set /p udefine= 
echo. 
echo *************************************************************** 
if %udefine%==1 (
    echo Give the parameters: 
    set /p argi= 
    set /p argii= 
    START /B java -jar JavaClient.jar %argi% %argii% 
) 

if %udefine%==e goto exit 

cls 
echo *************************************************************** 
echo. 
echo Thank You for using it 
echo. 
echo *************************************************************** 
echo Type [e] to exit or [b] to go back and select another option. 
echo. 
set /p udefine= 
echo. 
echo *************************************************************** 
if %udefine%==b goto top 
if %udefine%==e goto exit 
:exit 
cls 
echo *************************************************************** 
echo. 
echo Thank You for using it 
echo. 
echo *************************************************************** 
pause 
exit 

的问题是，如果我在第一次运行时，Java jar文件抛出异常，因为它不理解的变量参数％argi％和％argii％。我按[b]在选项菜单重新开始，我再次做同样的事情，瞧，它的工作！为什么？为什么它在第一次不起作用，并且如果我按[b]返回并再次将参数设置为每次都正常工作？

我启动的应用程序：

如果我杀了使用Ctrl-C的脚本，并重新打开它，它会再次有相同的行为......第一次错误，然后成功。 谢谢！

Answer 1

需要delayed expansion：

@echo off 
setlocal enableDelayedExpansion 
color 2f 
title "USERS MANAGEMENT IN A LAN" 
:top 
echo *************************************************************** 
echo. 
echo SELECT ACTIONS 
echo. 
echo *************************************************************** 
echo. 
echo [1] Ping the service     Params: unu 
echo [2] TBD 
echo. 
echo [e] Exit 
echo. 
echo *************************************************************** 
echo Enter the number of the website which you would like to go to: 
echo. 
set /p udefine= 
echo. 
echo *************************************************************** 
if %udefine%==1 (
    echo Give the parameters: 
    set /p argi= 
    set /p argii= 
    START /B java -jar JavaClient.jar !argi! !argii! 
) 

if %udefine%==e goto exit 

cls 
echo *************************************************************** 
echo. 
echo Thank You for using it 
echo. 
echo *************************************************************** 
echo Type [e] to exit or [b] to go back and select another option. 
echo. 
set /p udefine= 
echo. 
echo *************************************************************** 
if %udefine%==b goto top 
if %udefine%==e goto exit 
:exit 
cls 
echo *************************************************************** 
echo. 
echo Thank You for using it 
echo. 
echo *************************************************************** 
pause 
exit