Windows批处理文件有哪些不太为人所知,但很重要和有用的特性?

指南:

每个答案一个特征 给出特性的简短描述和示例,而不仅仅是文档链接 将答案限制在本地功能,即不需要额外的软件,如Windows资源包

澄清:这里我们指的是由cmd.exe处理的脚本,这是WinNT变体的默认值。

(请参见:Windows批处理文件:.bat vs .cmd?)


当前回答

输出一个空行:

echo.

其他回答

对于具有数字计数器的循环(输出1到10):

for /l %i in (1,1,10) do echo %i

There is also the EDLIN command. While it may be an old bastard tool once used for line-based text editing, the fact that it's controllable from the command line makes it rather useful for batch scripting, mostly because, just like any other case you'd be using EDLIN, it's the only tool available. After all, EDLIN is not a tool you would ordinarily want to use for text editing, unless you are somewhat masochistic. To quote Tim Patterson (the fellow who wrote it): "I was aghast when I heard that IBM was using it and not throwing it out the window."

注意:EDLIN将老式的EOF (1A)标记添加到它编辑的文件中。如果需要删除它们,可能必须使用DEBUG。

我发现你可以轻松地将命令输出重定向到文件中非常有用:

DIR *.txt > tmp.txt
DIR *.exe >> tmp.txt

单箭头创建或覆盖文件,双箭头追加文件。现在我可以在我的文本编辑器中打开tmp.txt,做各种各样的事情。

一行中包含多个命令,在很多情况下都很有用:

&用于组合两个命令,执行command1和command2 &&一个条件组合,如果command1成功完成,则执行command2 仅当command1未成功完成时才执行Command2。

例子:

:: ** Edit the most recent .TXT file and exit, useful in a .CMD / .BAT **
FOR /F %%I IN ('DIR *.TXT /B /O:-N') DO NOTEPAD %%I & EXIT


:: ** If exist any .TXT file, display the list in NOTEPAD, if not it 
:: ** exits without any error (note the && and the 2> error redirection)
DIR *.TXT > TXT.LST 2> NUL && NOTEPAD TXT.LST

抽取随机的文本行

@echo off

:: Get time (alas, it's only HH:MM xM

for /f %%a in ('time /t') do set zD1=%%a



:: Get last digit of MM

set zD2=%zD1:~4,1%



:: Seed the randomizer, if needed

if not defined zNUM1 set /a zNUM1=%zD2%


:: Get a kinda random number

set /a zNUM1=zNUM1 * 214013 + 2531011

set /a zNUM2=zNUM1 ^>^> 16 ^& 0x7fff


:: Pull off the first digit

:: (Last digit would be better, but it's late, and I'm tired)

set zIDX=%zNUM2:~0,1%


:: Map it down to 0-3

set /a zIDX=zIDX/3


:: Finally, we can set do some proper initialization

set /a zIIDX=0

set zLO=

set zLL=""


:: Step through each line in the file, looking for line zIDX

for /f "delims=@" %%a in (c:\lines.txt) do call :zoo  %zIDX%  %%a


:: If line zIDX wasn't found, we'll settle for zee LastLine

if "%zLO%"=="" set zLO=%zLL%

goto awdun


:: See if the current line is line zIDX

:zoo


:: Save string of all parms

set zALL=%*


:: Strip off the first parm (sure hope lines aren't longer than 254 chars)

set zWORDS=%zALL:~2,255%


:: Make this line zee LastLine

set zLL=%zWORDS%


:: If this is the line we're looking for, make it zee LineOut

if {%1}=={%zIIDX%} set zLO=%zWORDS%


:: Keep track of line numbers

set /a zIIDX=%zIIDX% + 1

goto :eof




:awdun

echo ==%zLO%==


:: Be socially responsible

set zALL=

set zD1=

set zD2=

set zIDX=

set zIIDX=

set zLL=

set zLO=

:: But don't mess with seed

::set zNUM1=

set zNUM2=

set zWORDS=