@echo off
setlocal enabledelayedexpansion
(for /f "delims=" %%a in (a.txt) do (
    set /p str=
    echo,%%a!str!
))<b.txt >c.txt
复制代码

@echo off
setlocal enabledelayedexpansion
(for /f "delims=" %%a in (b.txt) do (
    set /p str=
    echo,!str:日=%%a!
))<a.txt >c.txt
复制代码