Is there a regular What does it mean if there is a regular article to learn the regular article?

For some characters that are difficult to write, escape characters are added in front"\"method.

Vertical bar"|"That's what it means. This means that two matching conditions are logically "or" (or).

For example, the regular expression (him|her) match"it belongs to him"with"it belongs to her", but it can't be matched"it belongs to them."。Note:

This metacharacter is not supported by all software.

The simplest metacharacter is a dot, which matches any single character (note that line breaks are not included).

In a regular expression, it means to mark the next character as a special character, or a literal character, or a backward reference, or an octal escape. For example, 'n' matches the character 'n'. 'n' matches a line break.

The sequence 'matches' and ' matches "(

A regular expression describes a pattern of string matching, which can be used to check if a string contains a substring, replace a matching substring, or remove a string from a string that meets a certain condition.

column directory, dir *txt or ls **. in txttxt is not a regular expression, because the meaning of * is different from that of a regular expression.

A regular expression is a text pattern that consists of normal characters, such as characters a through z, and special characters, called metacharacters. A regular expression acts as a template to match a character pattern to the searched string.

Consists of all those printed and non-printed characters that are not explicitly designated as metacharacters. This includes all uppercase and lowercase letter characters, all numbers, all punctuation marks, and some symbols.

For example, 'n' matches the character 'n'. "n" matches a line break. The sequence 'matches' and ' matches "(

And what you say in this sentence is not in a regular expression, but an escape character of your programming language, i.e. w for w

Did the exclamation mark in front of you have a question mark before?

!pattern)

Negative pre-check, in any mismatched pattern

The string of the match lookup string. This is a non-acquisition match, that is, the match does not need to be acquired for later use. For example'windows (?95|98|nt|2000)'I can match.

windows ""windows", but it can't match"windows 2000"

windows"。Prelookup does not consume characters, that is, after one match occurs, the search for the next match starts immediately after the last match, rather than after the character that contains the prelook.

:pattern)

Matching patterns but not getting the results of the match, that is, this is a non-getting match and is not stored for later use. This is in use.

or"Character (|.)It's useful to combine the parts of a pattern. For example'industr(?:y|ies) is a comparison'industry|industries'

A shorter expression.

When the character is immediately followed by any one of the other limiters (*

Later, the matching pattern is non-greedy. The non-greedy mode matches as few strings as possible, while the default greedy mode matches as many strings as possible. For example, for strings"oooo"，'o+?'

A single will be matched"o", while'o+'All will be matched'o'。

Match any character any time, in other words, match any string.

A regular expression is a logical formula for string operations, that is, some specific characters and combinations of these specific characters are used to form a "rule string", which is used to express a filtering logic for strings.

It is a logical formula for string manipulation, that is, some specific characters and combinations of these specific characters are used to form a "rule string", which is used to express a filtering logic for strings. A regular expression is a text pattern that describes one or more strings to match when searching for text.

Regular expressions, also known as regular expressions. is a concept in computer science.

Regular expressions are often used to retrieve and replace text that fits a pattern (rule). Many programming languages support string manipulation with regular expressions. For example, there is a powerful regex engine built into Perl.

The concept of regular expressions was first popularized by tools in UNIX such as SED and GREP.

Regular expressions are usually abbreviated as "regex", and the singular number has regexp, regex, and the plural number has regexps, regexes, regexen.

If you haven't used regular expressions before, you may not be familiar with the term and concept. They're not as new as you might think, though.

Recall how you find files on your hard drive. You will definitely use ?and * characters to help find the file you're looking for

Characters match a single character in the file name, while * matches one or more characters. One such as'data?.dat'The following files can be found in the following mode:

If you use the * character instead of ?characters, the number of files found will be expanded. 'data*.dat'All of the following file names can be matched:

While this method of searching for files is certainly useful, it is also very limitedThe limited capabilities of the * wildcard give you an idea of what a regular expression can do, but it's more powerful and flexible.

To put it simply, a simple combination of various characters, called a regular expression, is used to implement a complex :

String matching, find what you need, so that you can extract what you want later.

This sounds simple, but in many real-world applications, there are thousands of strings to deal with, all kinds of complex characters, and each person's needs are endless, and the content that needs to be extracted is also infinite. However, if you do it manually, you can't write a common if else statement to determine whether the strings are equal or not.

With regularization, so many complex, extremely complex, and various requirements can be realized.

Regular expression learning experience.

Here are a few more practical examples:

Notepad++ Regular Expression Replacement Example 1: Replace the suffix of multiple files at once.

Notepad++ Regex Replacement Example 2: Replace multiple paths at once.

Notepad++ regex replacement example 3: Replace multiple listitems to sect4 at once

Notepad++ Regex Replacement Example 4: Add addicon prefix to each line.