DOS命令添加, 删除, 查询系统环境变量

::DOS命令添加, 查询系统环境变量
@echo off
echo 添加java环境变量
set regpath=HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Environment
set evname=JAVA_HOME
set javapath=c:\java\jdk
reg add "%regpath%" /v %evname% /d %javapath% /f

echo.
echo 查询path环境变量
REG QUERY "HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\Environment" /v Path

echo.
echo 查询evname环境变量
REG QUERY "HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\Environment" /v %evname%|findstr jdk

echo.
echo 获取path环境变量的具体值(具体值中不能有空格)
::delims=后面有一个空格
for /f "tokens=3 delims= " %%a in ('REG QUERY "HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\Environment" /v Path') do (
  set "a=%%a"
  echo %%a
)

echo.
echo 获取evname环境变量的具体值(具体值中不能有空格)
::delims=后面有一个空格
for /f "tokens=3 delims= " %%a in ('REG QUERY "HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\Environment" /v %evname%') do (
  set "a=%%a"
  echo %%a
)

echo.
echo 删除java环境变量
reg delete "%regpath%" /v "%evname%" /f
pause>nul
exit