在单独的行上显示数组元素

How do I print the array element of a Bash array on separate lines? This one works, but surely there is a better way:

如何在单独的行上打印Bash数组的数组元素?这一招行之有效，但肯定有更好的办法:

$ my_array=(one two three)
$ for i in ${my_array[@]}; do echo $i; done
one
two
three

Tried this one but it did not work:

尝试过这个，但是没有成功:

$ IFS=$'\n' echo ${my_array[*]}
one two three

5 个解决方案

#1

255

Try doing this :

试着这样做:

$ printf '%s\n' "${my_array[@]}"

The difference between $@ and $*:

$@与$*之间的差异:

Unquoted, the results are unspecified. In Bash, both expand to separate args and then wordsplit and globbed.

未引用的结果未说明。在Bash中，两者都扩展为分开的args，然后是wordsplit和globbed。
Quoted, "$@" expands each element as a separate argument, while "$*" expands to the args merged into one argument: "$1c$2c..." (where c is the first char of IFS).

引用“$@”将每个元素扩展为单独的参数，而“$*”扩展为合并为一个参数的args:“$1c$2c…”(其中c是IFS的第一个字符)。

You almost always want "$@". Same goes for "${arr[@]}".

你几乎总是想要“$@”。同样适用于“$ { arr[@]}”。

Always quote them!

总报价!

#2

Just quote the argument to echo:

引用这个论点来回应

( IFS=$'\n'; echo "${my_array[*]}" )

the sub shell helps restoring the IFS after use

子shell帮助在使用后恢复IFS。

#3

Using for:

使用:

for each in "${alpha[@]}"
do
  echo "$each"
done

Using history; note this will fail if your values contain !:

使用历史;注意，如果您的值包含以下内容，此操作将失败!

history -p "${alpha[@]}"

Using basename; note this will fail if your values contain /:

使用:;注意，如果您的值包含/:

basename -a "${alpha[@]}"

Using shuf; note that results might not come out in order:

使用shuf;注意，结果可能不是按顺序出来的:

shuf -e "${alpha[@]}"

#4

I tried the answers here in a giant for...if loop, but didn't get any joy - so I did it like this, maybe messy but did the job:

我在这里用一个巨大的盒子尝试了答案……如果是循环，但没有得到任何乐趣——我这样做了，可能有点乱，但做了工作:

 # EXP_LIST2 is iterated    
 # imagine a for loop
     EXP_LIST="List item"    
     EXP_LIST2="$EXP_LIST2 \n $EXP_LIST"
 done 
 echo -e $EXP_LIST2

although that added a space to the list, which is fine - I wanted it indented a bit. Also presume the "\n" could be printed in the original $EP_LIST.

虽然这给列表增加了一个空格，但这是可以的——我希望它缩进一点。也假定“\n”可以打印在原始的$EP_LIST中。

#5

Another useful variant is pipe to tr:

另一个有用的变体是管道到tr:

echo ${my_array[@]} | tr " " "\n"

echo ${my_array[@]

This looks simple and compact

这看起来简单而紧凑

#1

255