Regular Expressions - carding

First affixed two addresses, regular expression builder, and the third is the regular expression generated graphic resolution, and test the correctness of

1，http://www.bejson.com/othertools/regex_create/

2，http://tool.oschina.net/regex/#

3，https://regexper.com/#.

 

A constructor

var reg = new RegExp('\\bis\\b');

 

Second, the character class, with [] Building a simple class

'a1b3c4d7'.replace([\[abc]\g], 'P');

Output: 'P1P3P4d7'

 

Negated character class

'a1b3c4d7'.replace([\[^abc]\g], 'P');

Output: 'aPbPcPPP'

 

Third, the scope of the class [az]

Fourth, the predefined classes

V. border

eg: word boundary

'this is a boy'.replace(\bis\is, Q)

Output: 'this Q boy'

 

 Sixth, quantifiers

 

 

 

Seven, greedy

Eight groups

（boy）{3}=> boy boy boy

boy{3} => boyyy

 

eg: a packet of concepts 2015-12-23 12/23/2015 transformed into

‘2015-12-23’.replace(/(\d{4})-(\d{2})-(\d{2})/g, '$2$3$1')

Output: 12-23-2015

Nine, forward-looking

eg: word character is behind the data, only replaced the previous letter

Forward Prospects

 

 Negative Preview

 

 

 

Ten, exce, match, splice usage function