求助， 写一个批处理， 检测硬盘的空间， 并在硬盘空间少于500M时， 将当前硬盘空间信息写入一个txt文件

@echo off
setlocal enabledelayedexpansion
set /a free=500*1
>tmp.vbs echo result = wscript.arguments(1)/1024/1024
>>tmp.vbs echo Wscript.Echo wscript.arguments(0),result,int(result)
for %%i in (C D E F G H I J K L M N O P Q R S T U V W X Y Z) do (
if exist %%i:\ (
for /f "tokens=3" %%j in ('dir /-c %%i:\') do set num=%%j
if not "%%j"=="0" (
for /f "tokens=1-3 delims= " %%a in ('cscript //nologo tmp.vbs %%i: !num!') do (
echo 当前%%a盘剩余%%bM
if %%c lss !free! echo %date:~0,10%--%time:~0,8%--当前%%a剩余不足!free!M,约剩余%%bM>>剩余不足.txt
)
)))
del tmp.vbs
pause
exit /b