JavaScript QuickStart-ecmascript Local objects (REXEXP)

I. Overview

• The RegExp object represents a regular expression, which is a powerful tool for performing pattern matching on strings.
• A regular expression is a search pattern formed by a sequence of characters.
• When you search for data in text, you can use the search pattern to describe what you want to query.
• A regular expression can be a simple character, or a more complex pattern.
• Regular expressions can be used for all text search and text substitution operations.

Second, the grammar

/Regular expression body/ modifier (optional)

Third, using the string method

In JavaScript, regular expressions are typically used in two string methods: Search () and replace (). The string object has been introduced.

The Search () method retrieves the substring specified in the string, or retrieves a substring that matches the regular expression and returns the starting position of the substring.

The Replace () method is used to replace other characters with some characters in a string, or to replace a substring that matches a regular expression.

Iv. using the regular expression method with Test ()

The test () method is a regular expression method.

The test () method is used to detect whether a string matches a pattern and returns true if the string contains matching text, otherwise false.

Using EXEC ()

The exec () method is a regular expression method.

The exec () method is used to retrieve the matching of regular expressions in a string.

The function returns an array that holds the results of the match. If no match is found, the return value is null.

JavaScript QuickStart-ecmascript Local objects (REXEXP)