中国DOS联盟

wmic logicaldisk where caption="%usbdisk%" get size,freespace,caption | findstr /v /i "caption">%tmp%\disksize.tmp
for /f "tokens=2" %%a in (%tmp%\disksize.tmp) do set diskfreesize=%%a%~nx1

set diskfreesize=%%a%~nx1

set /a diskfreesize=%%a%~nx1

@echo off
for /f "tokens=2 delims==" %%a in ('wmic LogicalDisk where "DriveType='2'" get * /value ^| findstr /i "^size"') do set total=%%a
echo U盘总容量: %total%
>"%tmp%\cacl.vbs" echo wscript.echo %total%/2
for /f %%a in ('cscript /nologo "%tmp%\cacl.vbs"') do echo U盘总容量的一半: %%a

@echo off
for /f ... [/quote]
谢谢楼上这位大哥，这两天工作忙，今天才得以偷闲看到大哥的回复。
是这样的，我将大哥的代码改成下面这样进行测试时，遇到一个问题

[code]@echo on
for /f "tokens=2 delims==" %%a in ('wmic LogicalDisk where "DriveType='2'" get * /value ^| findstr /i "^size"') do set total=%%a
echo U盘总容量: %total%
>"%tmp%\cacl.vbs" echo wscript.echo %total%/1048576
for /f %%a in ('cscript /nologo "%tmp%\cacl.vbs"') do set /a size=%%a
echo U盘总容量: %size%MB
del %tmp%\cacl.vbs

C:\>set /a size=1927.71875
运算符不存在。

>"%tmp%\cacl.vbs" echo wscript.echo %total%/1048576

@echo off
for /f "tokens=2 delims==" %%a in ('wmic LogicalDisk where "DriveType='2'" get * /value ^| findstr /i "^size"') do set

total=%%a
>"%tmp%\cacl.vbs" echo wscript.echo left(%total%/(1024^^3),3)
for /f %%a in ('cscript /nologo "%tmp%\cacl.vbs"') do echo U盘总容量: %%aG
pause

@echo on
for /f "tokens=2 delims==" %%a in ('wmic LogicalDisk where "DriveType='2'" get * /value ^| findstr /i "^size"') do set total=%%a
echo U盘总容量: %total%
>"%tmp%\cacl.vbs" echo wscript.echo int(%total%/1048576)
for /f %%a in ('cscript /nologo "%tmp%\cacl.vbs"') do set /a size=%%a
echo U盘总容量: %size%MB
del %tmp%\cacl.vbs