中国DOS联盟

a.txt
aaaaaaaaaaaaa

输出为
ababababababab

即 把所有在偶数位置的a换成b~

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执行：HAT
操作：在帖子标题中增加搜索关键字
说明：原标题"文本替换问题"不利于论坛搜索
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[ Last edited by HAT on 2008-10-20 at 09:58 ]

Originally posted by huahua0919 at 2008-4-24 04:58 PM:
@echo off set str=aaaaaaaaaaaaa set str=%str:aa=ab% echo %str% pause

谢谢。。
原来就这么简单~ 想了很长时间的问题，看来是我想的太复杂了~

如偶数位不是a 就替换不了啊
@echo off&setlocal enabledelayedexpansion
for /f "delims=" %%i in (a.txt) do (
set "str=%%i"
call :lp
)
pause
goto :eof
:lp
set str1=!str:~%n%,1!
if defined str1 set/a n+=2&set str2=!str2!!str1!b&goto lp
set n=&echo !str2!
set str2=

[ Last edited by terse on 2008-4-24 at 05:21 PM ]

那你给的测试数据有问题……

文本输出问题，我最喜欢，也来凑个热闹了(考虑通用性哈)：
@echo off&setlocal enabledelayedexpansion set n=-2 :begin set /a n+=2 for /f "delims=" %%i in (a.txt) do ( set a=%%i&set a=!a:~%n%! if not "!a!"=="" ( set str=!a:~,1! set var=!var!!str!b goto begin ) echo !var! ) pause>nul&goto :eof

[ Last edited by zw19750516 on 2008-4-24 at 11:31 PM ]

晕，上面还是没考虑到字符总数是奇数时会多一个b的情况，修改如下：
echo off&setlocal enabledelayedexpansion set n=-2&set b=b :begin set /a n+=2 for /f "delims=" %%i in (a.txt) do ( set a=%%i&set a=!a:~%n%! if "!a:~1!"=="" set "b=" if not "!a!"=="" ( set str=!a:~,1! set var=!var!!str!!b! goto begin ) echo !var! ) pause>nul&goto :eof

通用加效率
@echo off for /f "delims=" %%a in (a.txt) do ( set str=%%a&set "num=" call :loop ) pause :loop set num=%num%%str:~0,1%b set str=%str:~2% if not defined str echo %num%&goto :eof goto loop

考虑奇数行
: @echo off for /f "delims=" %%a in (a.txt) do ( set str=%%a&set "num=" call :loop ) pause :loop if not "%str:~1,1%"=="" (set num=%num%%str:~0,1%b) else set num=%num%%str% set str=%str:~2% if not defined str (echo %num%&goto :eof) goto loop