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 ]
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| Rater | Score | Time |
|---|---|---|
| ccwan | +5 | 2006-12-17 06:45 |
| zh159 | +5 | 2006-12-17 06:52 |
| redtek | +5 | 2006-12-17 21:20 |
| lianjiang2004 | +4 | 2006-12-17 21:30 |
| HUNRYBECKY | +5 | 2007-03-17 11:46 |
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| fengjian | +1 | 2007-10-31 18:01 |
| upsco | +1 | 2007-11-21 21:18 |
| xiaohacker | +2 | 2007-12-23 20:32 |
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