嵌套在if语句中时，启动cmd在Windows批处理文件中无法正常执行

Question

无论出于何种原因，此命令有效：

SET QUERY="heat wave"
START /d "C:\Program Files (x86)\Google\Chrome\Application" chrome.exe https://www.google.com/search?q=%QUERY: =+%

但这不是：

SET SWITCH=1
IF %SWITCH%==1 (
SET QUERY="heat wave"
START /d "C:\Program Files (x86)\Google\Chrome\Application" chrome.exe https://www.google.com/search?q=%QUERY: =+%
)

Answer 1

这里的关键是enabledelayedexpansion

setlocal enabledelayedexpansion
SET SWITCH=1
IF %SWITCH%==1 (
SET QUERY="heat wave"
START /d "C:\Program Files (x86)\Google\Chrome\Application\chrome.exe" https://www.google.com/search?q=!QUERY: =+!
)

有关delayedexpansion的更多信息请参阅cmdline的set /?。

也可以没有delayedexpansion加倍最后的%并召唤开始。

SET SWITCH=1
IF %SWITCH%==1 (
SET QUERY="heat wave"
call START /d "C:\Program Files (x86)\Google\Chrome\Application\chrome.exe" https://www.google.com/search?q=%%QUERY: =+%%
)