我想读取一个包含多个(未终止的)Kafka 主机的字符串,并使用 cmd for
将它们列出在单独的行中。
字符串如下:
host1:9092,host2:9092,host3:9092,...
我所拥有的是:
set /p BOOTSTRAPSERVERS="Bootstrap servers with port, separated by comma(by default localhost:9092): "
REM echo "%BOOTSTRAPSERVERS%"
if "%BOOTSTRAPSERVERS%"=="" set BOOTSTRAPSERVERS="localhost"
echo All the servers to connect:
FOR /F "usebackq delims=," %%i in (`echo %BOOTSTRAPSERVERS%`) do (
echo %%i
echo.
)
但是,我只将所有主机放在一行中,以空格分隔:
All the servers to connect:
host1:9092 host2:9092 host3:9092
为什么?
如果我打开@echo on
,我会看到这个,这是没有意义的:
set /p BOOTSTRAPSERVERS="Bootstrap servers with port, separated by comma(by default localhost:9092): "
Bootstrap servers with port, separated by comma(by default localhost:9092): host1:9092,host2:9092,host3:9092
REM echo "host1:9092,host2:9092,host3:9092"
if "host1:9092,host2:9092,host3:9092" == "" set BOOTSTRAPSERVERS="localhost"
echo All the servers to connect:
All the servers to connect:
FOR /F "usebackq delims=," %i in (`echo host1:9092 host2:9092 host3:9092`) do (
echo %i
echo.
)
(
echo host1:9092
echo.
)
host1:9092
如果仔细观察,当 %BOOTSTRAPSERVERS%
没有双引号时,echo
会将字符串从逗号分隔变为空格分隔。
如果是双引号,输出将为:
"host1:9092
为什么?
是否有更好的方法来用分隔符分割字符串?
最佳答案
要按标准分隔符(空格、制表符、逗号)分割字符串,您可以使用普通的 for
循环(无 /f
):
set "bootstrapservers=host1:9092,host2:9092,host3:9092"
for %%a in (%bootstrapservers%) do echo %%a
输出:
host1:9092
host2:9092
host3:9092
请注意 set
命令的语法(这样引号就不会成为值的一部分)。相同的语法适用于 set/p
:set/p "var=Prompt:"
关于batch-file - cmd 批处理 - usebackq 为 : string to split altered from comma separated to space separated,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/59771342/