js reges code example
Example 1: javascript regex
// \d Any digit character
// \w An alphanumeric character (“word character”)
// \s Any whitespace character (space, tab, newline, and similar)
// \D A character that is not a digit
// \W A nonalphanumeric character
// \S A nonwhitespace character
// . Any character except for newline
// /abc/ A sequence of characters
// /[abc]/ Any character from a set of characters
// /[^abc]/ Any character not in a set of characters
// /[0-9]/ Any character in a range of characters
// /x+/ One or more occurrences of the pattern x
// /x+?/ One or more occurrences, nongreedy
// /x*/ Zero or more occurrences
// /x?/ Zero or one occurrence
// /x{2,4}/ Two to four occurrences
// /(abc)/ A group
// /a|b|c/ Any one of several patterns
// /\d/ Any digit character
// /\w/ An alphanumeric character (“word character”)
// /\s/ Any whitespace character
// /./ Any character except newlines
// /\b/ A word boundary
// /^/ Start of input
// /$/ End of input
Example 2: javascript regex
//Declare Reg using slash
let reg = /abc/
//Declare using class, useful for buil a RegExp from a variable
reg = new RegExp('abc')
//Option you must know: i -> Not case sensitive, g -> match all the string
let str = 'Abc abc abc'
str.match(/abc/) //Array(1) ["abc"] match only the first and return
str.match(/abc/g) //Array(2) ["abc","abc"] match all
str.match(/abc/i) //Array(1) ["Abc"] not case sensitive
str.match(/abc/ig) //Array(3) ["Abc","abc","abc"]
//the equivalent with new RegExp is
str.match('abc', 'ig') //Array(3) ["Abc","abc","abc"]