批处理BAT文件中FOR语句中echo的显示问题

为什么要用FOR呢，下面的代码可以实现你的要求，就是将 c:\ss\aaa.pdf 建立一个新的拷贝 c:\ews\result\20111011_1215.pdf
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set "str=2011-10-11 12:15"
set str1=%str:~0,4%%str:~5,2%%str:~8,2%_%str:~11,2%%str:~14,2%
echo %str1%
copy c:\ss\aaa.pdf c:\ews\result\%str1%.pdf

setlocal enabledelayedexpansion
for /f "delims=" %%a in ('dir /s/b/a-d c:\ss\aaa.pdf') do (
echo %%~ta
set str=%%~ta
echo !str:~0,4!
echo !str:~5,2!
echo !str:~8,2!
echo !str:~11,2!
echo !str:~14,2!
set str1=!str:~0,4!!str:~5,2!!str:~8,2!_!str:~11,2!!str:~14,2!
echo
copy c:\ss\aaa.pdf c:\ews\result\.pdf
start D:\"Foxit Software"\"Foxit Phantom"\"Foxit Phantom.exe" c:\ews\result\.pdf
)