Regular Expressions of JavaScript (2)

One, greedy mode and non-greedy mode

(1) Greedy mode

• If the regular expression is \d{3,6}. The string ' 123456789 ' will result in as many matches as possible

　　

(2) Non-greedy mode

• Only need to add after the quantifier? To represent as few matches as possible for non-greedy matches

Two, group

Group Plus ()

　　

　　

or the concept of |

　　

Three, reverse reference

After grouping, it is referenced by a variable, such as

If you want to ignore the grouping, you need to add (?) in the grouping. ：）

Four, forward-looking

　　

Regular Expressions of JavaScript (2)