went

@echo off
setlocal enabledelayedexpansion
set "n=0"
for /r %%i in (*) do (
	if not "%%~xi"=="" if "!%%~xi!"=="" (
		set "%%~xi=true"
		set /a "n+=1"
		echo %%~xi
	) 
)
echo 共%n%种类型
pause&exit
复制代码

went

回复 6# qixiaobin0715

表示当前后缀名未定义,也就是第一次出现