Detailed explanation of operators in the regular expression tutorial

This article mainly introduces the operators and descriptions in the regular expression tutorial, and analyzes common operators and their functions in detail, for more information about operators in regular expressions, see the following example. We will share this with you for your reference. The details are as follows:

1. common characters

Including all printed and non-printed characters that are not explicitly specified as metacharacters, such as uppercase and lowercase letters, numbers, and punctuation marks.

II. metacharacters

Metacharacters are characters with special meanings in regular expressions. Because Metacharacters have special meanings in regular expressions, they cannot represent themselves. they must be escaped by adding a backslash prefix to them, the escape sequence will match the character itself rather than its special metacharacters. For example, [indicates the start of a character set combination. if you want to match [in a regular expression, you need to reference \ [in this way to represent [itself.

Here we only classify some operators used in regular expressions according to different functions, which is not necessarily accurate, just to illustrate the operators in regular expressions.

I hope this article will help you learn regular expressions.

For more details about operators and descriptions in the regular expression tutorial, please refer to the PHP Chinese website!