javascript - Regex capturing : get the whole match in a capturing group -

i can't capture work :

my aim capture in string length of first capture group :

var regex = /(_)?;([\w]+);([\w]+);/; var string = "____;foo;bar;"; var matches = regex.exec(string);  console.log(matches); // outputs  ["_;foo;bar;", "_", "foo", "bar"] 

as can see, matches[1] contains capturing group undescores, gives me matched character, not underscores. expect result :

["_;foo;bar;", "_____", "foo", "bar"] 

is there way achieve regex ? prefer avoid splitting string ; ...

you use pattern this:

/(_*);(\w+);(\w+);/ 

which give you:

["_____;foo;bar;", "_____", "foo", "bar"] 

this pattern match following sequence:

• zero or more underscores, captured in group 1
• a semicolon
• one or more word characters, captured in group 2
• a semicolon
• one or more word characters, captured in group 3
• a semicolon