Here is a list of the methods associated with RegExp along with their description. In the following sections, we will have a few examples to demonstrate the usage of RegExp properties. The index at which to start the next match. Specifies the function that creates an object's prototype. Here is a list of the properties associated with RegExp and their description. Performs a global matchthat is, find all matches rather than stopping after the first match. Specifies that if the string has newline or carriage return characters, the ^ and $ operators will now match against a newline boundary, instead of a string boundary Several modifiers are available that can simplify the way you work with regexps, like case sensitivity, searching in multiple lines, etc. Matches any of the alternatives specified Matches a single character outside the given set Matches a single character in the given set Sr.No.Ī whitespace character (space, tab, newline) The following table lists a set of metacharacters which can be used in PERL Style Regular Expressions. The control character ^X for example, \cJ is equivalent to the newline character \nĪ metacharacter is simply an alphabetical character preceded by a backslash that acts to give the combination a special meaning.įor instance, you can search for a large sum of money using the '\d' metacharacter: /(+)000/, Here \d will search for any string of numerical character. The Unicode character specified by the hexadecimal number xxxx for example, \u0009 is the same as \t The Latin character specified by the hexadecimal number nn for example, \x0A is the same as \n It matches any string containing a p followed by zero or more instances of the sequence hp. It matches any string enclosed within and. It matches any string containing exactly two characters.
It matches any string containing p, followed by any character, in turn followed by another p. It matches any string not containing any of the characters ranging from a through z and A through Z. It matches any string with p at the beginning of it.įollowing examples explain more about matching characters. It matches any string with p at the end of it. It matches any string containing a sequence of at least two p's. It matches any string containing a sequence of two or three p's. It matches any string containing a sequence of N p's It matches any string containing at most one p. It matches any string containing zero or more p's. It matches any string containing one or more p's. The +, *, ?, and $ flags all follow a character sequence. Each special character has a specific connotation. The frequency or position of bracketed character sequences and single characters can be denoted by a special character. The ranges shown above are general you could also use the range to match any decimal digit ranging from 0 through 3, or the range to match any lowercase character ranging from b through v. It matches any character from lowercase a through uppercase Z. It matches any character from uppercase A through uppercase Z. It matches any character from lowercase a through lowercase z. It matches any decimal digit from 0 through 9. Sr.No.Īny one character not between the brackets. They are used to find a range of characters. Pattern − A string that specifies the pattern of the regular expression or another regular expression.Īttributes − An optional string containing any of the "g", "i", and "m" attributes that specify global, case-insensitive, and multi-line matches, respectively.īrackets () have a special meaning when used in the context of regular expressions. Here is the description of the parameters − Var pattern = new RegExp(pattern, attributes) SyntaxĪ regular expression could be defined with the RegExp () constructor, as follows − The JavaScript RegExp class represents regular expressions, and both String and RegExp define methods that use regular expressions to perform powerful pattern-matching and search-and-replace functions on text. A regular expression is an object that describes a pattern of characters.