@echo off
set "url=www.mzwu.com"
echo 1.字符串截取
echo %url:~4,4%
echo %url:~4,-4%
echo %url:~-8,4%
echo %url:~-8,-4%
echo %url:~,4%
echo %url:~,-4%
echo %url:~4%
echo %url:~-8%
echo.
echo 2.字符串替换，将mzwu替换为163
echo %url:mzwu=163%
pause>nul
原文：https://www.cnblogs.com/cbugs/p/9003674.html