What are the main regular expressions?

Mainly include character matching, quantifiers and repetitions, character classes and ranges, boundary matching, grouping and references, zero-width assertions, replacement and capture, etc. Detailed introduction: 1. Character matching: Regular expressions can be used to match specific characters, such as letters, numbers, blank characters, etc.; 2. Quantifiers and repetition: Regular expressions can specify the number or range of character repetitions, such as matching 0 times. or multiple times, match one or more times, match a specific number of times, etc.; 3. Character class and range: Regular expressions can use character classes to match a group of characters, or use ranges to specify the range of characters, etc.

Operating system for this tutorial: Windows 10 system, Dell G3 computer.

What are the main aspects of regular expressions?

Regular expressions mainly include the following aspects:

Character matching: Regular expressions can be used to match specific characters. Such as letters, numbers, blank characters, etc.

Quantifiers and repetition: Regular expressions can specify the number or range of character repetitions, such as matching 0 or more times, matching 1 or more times, matching a specific number of times, etc.

Character classes and ranges: Regular expressions can use character classes to match a group of characters, such as matching any numbers, letters, special symbols, etc. You can also use ranges to specify the range of characters, such as matching a to z. letters between.

Boundary matching: Regular expressions can be used to match the boundaries of strings, such as matching the beginning and end of a line.

Grouping and quoting: Regular expressions can use grouping to organize matching parts, and can reference already matched content through quoting.

Zero-width assertion: Regular expressions can use zero-width assertions to specify matching positions, such as positive positive lookahead assertions, negative lookahead assertions, etc.

Replacement and capture: Regular expressions can be used to replace strings, and grouping can also be used to capture matching content.

These are the main contents of regular expressions. By combining and applying these elements, complex patterns can be constructed to match and process strings. Different programming languages ​​and tools may have slightly different syntax and features, but the underlying principles and functionality are similar.

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