@echo off
REM 分割字符串
set str=文件名1=文件名2=文件名3=文件名4=文件名5.doc
for /f "tokens=1,2,4,5,* delims==" %%a in ("%str%") do (

set c1=%%a
set c2=%%b
set c3=%%c
set c4=%%d
set c5=%%e
)
echo %c3%=%c1%=%c2%=%c3%=%c4%>d:\a.txt
pause