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@echo on & setlocal EnableDelayedExpansion
for /f "tokens=2 delims=[" %%i in ('ping g.cn -n 1 ') do set ip=%%i
for /f "tokens=2 delims=]" %%i in ('ping g.cn -n 1 ') do set tmp=%%i
set tmp=]%tmp%
字符串替换
set ip=%ip:%tmp%=%   '错误
变量ip替换tmp为空,不知为什么