win_bat: FOR syntax learning

FOR syntax learning

 

 

 

 

一、代码及注释

 

@echo off

dir
g:
cd .\tmpWorkspaces






rem        --  FOR Learning  --






rem    ==    for /d  d=directory; list names of directories in the given directories
rem    for /d %%i  in (g:\*) do echo %%i


rem    ==    for /r  r=recursive directory;  list specified file names in current directory and its subdirectories.
rem    for /r g:\  %%i  in (*.exe) do  echo %%i


rem    ==    for /l  l= a sequence digit; output a sequence of digits.
rem    for /l %%i in (1,2,10) do echo %%i


rem    ==    for /f  f = file contents; deal with contets of specified files.
rem    FOR    /F "eol=; tokens=1,2* delims=,- " %%i in (g:\tmpWorkspaces\testfor.txt) do echo %%i %%j %%k
rem    for    /F "tokens=1,2,3,4* " %%i in (g:\tmpWorkspaces\testfor.txt) do echo %%i %%j %%k %%l
rem    for    /F "tokens=1,2,3,4*" %%i in (g:\tmpWorkspaces\testfor.txt) do echo %%i %%j %%k %%l
rem    for    /f "eol== tokens=1,2,3,4* "  %%a in (g:\tmpWorkspaces\testfor.txt) do echo %%a %%b %%c %%d






rem    ENHANCED




rem    == enhanced-part-1


goto explanation

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.

:explanation




echo enhanced-part-1
rem    ==    %%~ni： print file name only.
rem    FOR /F "delims==" %%i IN ('dir /b') DO @echo %%~ni


rem    ==    %%~fnxazi： f: full path name; n:file name; x:file extension name;
rem    a:file attributes; z:file size; i:delete quotes(")
FOR    /F  "delims=="  %%i  IN ('dir /b')  DO  @echo %%~fnxazi




rem        == enhanced-part-2


goto nl

说明：这里是重点内容！


%I        The %~ syntax is terminated by a valid FOR variable name('I'是for中‘声明的变量名).
%I        'I'是for中‘声明的变量名’；如果声明for声明的变量名是y；则扩展为'%~y'；


    'm'是for中声明的变量名；则有

        扩展            功能

        %~m         - expands %m removing any surrounding quotes (")
        %~fm        - expands %m to a fully qualified path name
        %~dm        - expands %m to a drive letter only
        %~pm        - expands %m to a path only
        %~nm        - expands %m to a file name only
        %~xm        - expands %m to a file extension only
        %~sm        - expanded path contains short names only
        %~am        - expands %m to file attributes of file
        %~tm        - expands %m to date/time of file
        %~zm        - expands %m to size of file
        ...            ...


:nl




echo enhanced-part-2
rem    ==    %%~ny： print file name only.
rem    FOR /F "delims==" %%y IN ('dir /b') DO @echo %%~ny


rem    ==    %%~fnxazy： f: full path name; n:file name; x:file extension name;
rem    a:file attributes; z:file size; i:delete quotes(")
FOR    /F  "delims=="  %%y  IN ('dir /b')  DO  @echo %%~fnxazy

 

 

 

 

二、参考资料

 

　　1、help(environment: cmd.exe)     G:\tmpWorkspaces>for /?

 

　　2、bat 批处理 for 入门　　https://www.jb51.net/article/134025.htm