I want to Select specific text between two strings using regex.
e.g:
foo I have four toys bar //single line
foo //multiline
I
have
four
toys
bar
foo I have three pets bar
foo
I
have
three
pets bar
How to select text between "foo" and "bar" with specific word containing "four"
Output:
I have four toys
I
have
four
toys
My code:
foo[\s\S]*?(four)[\s\S]*?bar
My code is working fine but problem is that when when "four" word does not comes between "foo" and "bar" it is selecting all text till "four" word
foo I have three pets bar
foo I have four toys bar
foo
I
have
three
pets bar
I just want text between "foo" and "bar" when it is containg specific word "four"
We can use the following regex pattern, in dot all mode:
\bfoo\s+(?:(?!\bbar\b).)*?\s+four\s+(?:(?!\bfoo\b).)*?\s+bar
var input = `foo I have four toys bar
foo
I
have
four
toys
bar
foo I have three pets bar
foo
I
have
three
pets bar`;
var matches = input.match(/\bfoo\s+(?:(?!\bbar\b).)*?\s+four\s+(?:(?!\bfoo\b).)*?\s+bar/gs)
.map(x => x.replace(/^foo\s+|\s+bar$/g, ""));
console.log(matches);An explanation to this complex regex pattern might be helpful here:
\bfoo\s+ match 'foo' followed by one or more whitespace characters
(?:(?!\bbar\b).)*? match any content WITHOUT encountering 'bar'
\s+four\s+ match 'four' surrounded by whitespace
(?:(?!\bfoo\b).)*? match any content WITHOUT encountering 'foo'
\s+bar whitespace followed by ending 'bar'
Note that due to the way match() behaves, we also have a map step where we strip off leading foo and ending bar from every match.