中国DOS联盟

::code by lxmxn @ cn-dos.net .

::目的：帮助新手们更好的理解变量字符截取功能.

::Date 2006-12-16 .

::说明：有的变量截取之后值为空，这是正常的.

@echo off&setlocal EnableDelayedexpansion

::设置变量var的值：

set var=0123456789ABCDEF

call :begin

for /l %%a in (1,3,15) do (

    for /l %%b in (1,4,15) do (

        call :printf %%a %%b

    )

)

call :begin

for /l %%a in (1,4,15) do (

    for /l %%b in (-1,-3,-15) do (

        call :printf  %%a %%b

    )

)

call :begin

for /l %%a in (-2,-3,-15) do (

    for /l %%b in (1,4,15) do (

        call :printf  %%a %%b

    )

)

call :begin

for /l %%a in (-1,-4,-15) do (

    for /l %%b in (-2,-3,-15) do (

        call :printf  %%a %%b

    )

)

pause

endlocal&cls&echo.

echo 演示结束了，任意键退出……

pause>nul

goto :eof



::输出结果：

:printf

    echo %%var:~%1,%2%%	截取之后的字符为:	!var:~%1,%2!

    goto :eof



::清理屏幕：

:begin

    echo\&pause&cls&echo.

    echo 			变量var的值为:	%var%

    echo.

    goto :eof

　　In fact, the character interception function of variables in CMD is very practical, but some friends haven't really understood the rules inside. So today I specially wrote the following code, hoping to help novice friends understand the character interception function of variables under CMD.

::code by lxmxn @ cn-dos.net .

::Purpose: To help novices better understand the variable character interception function.

::Date 2006-12-16 .

::Description: Some variables may have empty values after interception, which is normal.

@echo off&setlocal EnableDelayedexpansion

::Set the value of variable var:

set var=0123456789ABCDEF

call :begin

for /l %%a in (1,3,15) do (

    for /l %%b in (1,4,15) do (

        call :printf %%a %%b

    )

)

call :begin

for /l %%a in (1,4,15) do (

    for /l %%b in (-1,-3,-15) do (

        call :printf  %%a %%b

    )

)

call :begin

for /l %%a in (-2,-3,-15) do (

    for /l %%b in (1,4,15) do (

        call :printf  %%a %%b

    )

)

call :begin

for /l %%a in (-1,-4,-15) do (

    for /l %%b in (-2,-3,-15) do (

        call :printf  %%a %%b

    )

)

pause

endlocal&cls&echo.

echo The demonstration is over, press any key to exit...

pause>nul

goto :eof



::Output result:

:printf

    echo %%var:~%1,%2%% The intercepted character is:	!var:~%1,%2!

    goto :eof



::Clear the screen:

:begin

    echo\&pause&cls&echo.

    echo 			The value of variable var is:	%var%

    echo.

    goto :eof

　　　　　　Click here to download the attachment (Getstr.rar)

Last edited by lxmxn on 2007-10-31 at 06:33 PM ]

Thanks to brother lxmxn, it has been of great help to beginners like us!

It is suggested that everyone copy the code, save it as a BAT file, and then add a tab character with TAB before "The character after interception is" and "The value of variable var is", so that the display will be neat.

　　Re ccwan :
　
　　Sweat, are you still a newbie?
　　Thanks for the plus points and encouragement. ^_^

　　Re zh159 :

　　Thanks for your proposal and plus points, brother.
　　I spent a long time re-editing the post, but unfortunately, I still didn't achieve a neat display effect in the end. Finally, I had to let everyone download it as an attachment.

So wonderful～～
Why did the font become smaller?

Originally posted by redtek at 2006-12-17 07:47:
So wonderful~~
Why did the font become smaller?

　　What you mentioned about the font becoming smaller, what exactly are you referring to? My theme's font has become larger instead.

Good stuff, learning.

Learned. Good post.

If the characters are too small and hard to read, you can hold down the Ctrl key and then scroll the mouse wheel upward to make them larger, and scroll downward to make them smaller.

　　Adjusted the font, let's see how big the font is now.
　
　　I specifically adjusted the font to be relatively large yesterday, but today when I came to the forum, it suddenly became very small. I don't know the reason.

Classic, newcomers are in for a treat! Hehe

Wonderful~~Bump up this great post~:)

Good stuff, so good that it's hard to describe. It turns out that batch processing has such detailed functions.