For 的使用

1.遍历指定文件夹下扩展名是txt的所有的文件(包括子文件夹)

FOR /R C:\gcz %%G IN (*.txt) DO (
echo %%G
echo "hehheheheh"
)

2.读入文件中的每一行, 并找出包含特殊字符的行

for /f %%a in (c:\1.txt) do (

echo %%a > Content.txt

findstr /I /R "^REM" "Content.txt"

if NOT ERRORLEVEL 1 (
echo result is : %%a
)

)

注意:
在循环中可以使用ERRORLEVEL作为判断条件, 但不能使用 %ERRORLEVEL%作为判断条件, 因为批处理是要进行预处理的，%errorlevel%会被预处理成0.

if ERRORLEVEL 1 表示>=1, 不是表示等于1




In addition, substitution of FOR variable references has been enhanced.
You can now use the following optional syntax:

    %~I         - expands %I removing any surrounding quotes (")
    %~fI        - expands %I to a fully qualified path name
    %~dI        - expands %I to a drive letter only
    %~pI        - expands %I to a path only
    %~nI        - expands %I to a file name only
    %~xI        - expands %I to a file extension only
    %~sI        - expanded path contains short names only
    %~aI        - expands %I to file attributes of file
    %~tI        - expands %I to date/time of file
    %~zI        - expands %I to size of file
    %~$PATH:I   - searches the directories listed in the PATH
                   environment variable and expands %I to the
                   fully qualified name of the first one found.
                   If the environment variable name is not
                   defined or the file is not found by the
                   search, then this modifier expands to the
                   empty string

The modifiers can be combined to get compound results:

    %~dpI       - expands %I to a drive letter and path only
    %~nxI       - expands %I to a file name and extension only
    %~fsI       - expands %I to a full path name with short names only
    %~dp$PATH:I - searches the directories listed in the PATH
                   environment variable for %I and expands to the
                   drive letter and path of the first one found.
    %~ftzaI     - expands %I to a DIR like output line

In the above examples %I and PATH can be replaced by other valid
values.  The %~ syntax is terminated by a valid FOR variable name.
Picking upper case variable names like %I makes it more readable and
avoids confusion with the modifiers, which are not case sensitive.


更详细的信息请参考: http://www.ss64.com/nt/for.html