JavaScript RegExp (RegExp) Object

Regular expressions are a series of characters that form a search pattern.

When searching for data in the text, you can use this search pattern to describe the content to be searched.

A regular expression can be a single character, or a more complex pattern.

RegExp object

A regular expression is an object that describes a character pattern.

RegExp The constructor creates a regular expression object that matches text with the pattern.

Syntax:

new　RegExp(pattern,　modifiers);

or simply

/pattern/modifiers;

var　regex　=　/w3codebox/g

Example explanation:

You can find in ourIn the JavaScript RegExp tutorialLearn more about regular expressions.

Modifiers are used to perform global search, case-sensitive, and multi-line search:

Modifier	Description
g	Execute global matching, that is, find all matches instead of stopping after the first match
i	Execute case-insensitive matching
m	Execute multi-line matching

Brackets are used to find a series of characters:

Expression	Description
[abc]	Matches any character in brackets
[^abc]	Matches any character not in brackets
[0-9]	Matches any number between brackets
[^0-9]	Matches any character not between parentheses (any non-digit character)
(x\|y)	Matches any specified alternative

A meta-character is a letter character followed by a backslash to make the combination have a special meaning:

Meta-character	Description
.	Matches any single character except the newline character \n.
\w	Matches letters and digits [0-9a-zA-Z]
\W	Matches any non-letter and non-digit
\d	Matches any digit[0-9]
\D	Matches any non-digit[^0-9]
\s	Matches space, newline, and indentation characters
\S	Matches non-space, newline, and indentation characters
\b	At the beginning of the word/End found the match item
\B	Matches not at the beginning of a word/End of the match item
\0	Matches a single NUL character
\n	Matches the newline
\f	Matches the form feed
\r	Matches the carriage return
\t	Matches the tab
\v	Matches the vertical tab
\xxx	Matches the character specified by the octal number xxx
\xdd	Matches the character specified by the hexadecimal number dd
\uxxxx	Matches the Unicode character specified by the hexadecimal number xxx

The frequency or position of a sequence of bracket characters and a single character can be represented by special characters:

Quantifier	Description
z+	Matches any string containing at least onezString
z*	Matches any string containing zero or morezString
z?	Matches any string containing zero or onezString
z{X}	Matches a string containing a sequence of X 'z' characters
z{X,Y}	Matches a string containing a sequence of X to Y 'z' characters
z{X,}	A string that contains at least X z sequences.
z$	Matches any string that starts withzA string that ends with
^z	Matches any string that starts withzA string that starts with
?=z	Matches a string followed by a specific stringzany string
?!z	Matches any string not followed by a specific stringzof the string

The following table lists the properties of the RegExp object:

Properties	Description
constructor	Returns the function that creates the prototype of the RegExp object
global	Checks if the 'g' modifier is set
ignoreCase	Checks if the 'i' modifier is set
lastIndex	Starts the index of the next match
multiline	Checks if the 'm' modifier is set
source	Returns the text of the RegExp pattern

The following table lists the methods of the RegExp object:

Method	Description
exec()	Searches for a match in the string parameter
test()	Tests whether the string parameter matches and returns a boolean value
toString()	Returns a string representation of the specified object