批处理的问题
@echo off
echo.
for %%i in (e:\batch\test\*.*) do (
echo "%%~xi"
)
echo OK
pause>nul


在这里 echo "%%~xi"
输出的是所有文件的扩展名

我想问的是为什么是文件的扩展名？

------解决方案--------------------
因为当初微软的程序员就是这样开发操作系统的

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