Extract string between parentheses

问题

I've been trying to extract the substring in between parentheses (including parentheses) from:

"WHITE-TAILED TROPIC-BIRD _Phaëthon lepturus_ (Hawaiian name—koae)"

I tried this:

str=$(echo $1 | sed 's/.*\(\([^)]*\)\).*/\1/');
echo $str

What I wanted to get was:

"(Hawaiian name—koae)"

However, I've been getting an error called:

bash: syntax error near unexpected token `('

What do I do wrong?

回答1:

You may use

sed -n 's/.*\(([^()]*)\).*/\1/p'

Here,

-n - suppresses default line output
.*\(([^()]*)\).* - matches any text, then captures into Group 1 a (, then 0 or more chars other than ( and ), then a ), and then again .* matches any text to the end of the string
/\1/ - replaces the whole match with the contents of Group 1
p - prints the result.

See online demo

In a script called script.sh:

#!/bin/bash
str=$(echo "$1" | sed -n 's/.*\(([^()]*)\).*/\1/p');
echo "$str"

Called like

bash ./script.sh "WHITE-TAILED TROPIC-BIRD _Phaëthon lepturus_ (Hawaiian name—koae)"

Result: (Hawaiian name—koae)

回答2:

echo "WHITE-TAILED TROPIC-BIRD _Phaëthon lepturus_ (Hawaiian name—koae)" | \
cut -d'_' -f3 | sed s'@^ @@'

If you've got good delimiters, then it is much easier to get parts of lines with cut, than with sed. I only really use sed for replacing characters when I know exactly where they are. For more complex operations, I will usually have to get a piece of text out of the file by inserting carriage returns before and after it with ed, (thus putting it on its' own line, which I can then rip out easily) make the minor changes to it that I want with sed, and then use ed to put it back in.

来源：https://stackoverflow.com/questions/63227813/extract-string-between-parentheses

标签

sed