whitespace character

CharactersMeaning: For a character, it is usually expressed as literal meaning that the next character is a special character and is not interpreted.For example:/b/matches the character ' B ', by adding a backslash in front of B, which is/b/, the

DefinedIn essence, a regular expression (or RE) is a small, highly specialized programming language,(in Python) it is embedded in Python and is implemented through the RE module. The regular expression pattern isCompiled into a sequence of bytecode,

Predefined term Matches \ t Horizontal tab \b Backspace \v Vertical tab \f Form Feed \ r Carriage return \ n Newline

No matter what language, the regular expression of the processing methods are very flexible and efficient, especially for some strings of the crawl, filtering aspects, more obvious advantages.Regular expressions are often simpler to do, and a few

Match format^ matches the beginning of the string$ matches the end of a string. All characters except line breaks[...] Used to represent a set of characters, listed separately: [AMK] matches ' a ', ' m ' or ' K '[^..] Characters not in []: [^ABC]

A line break matches a newline character. Equivalent to \x0a and \CJ.+ \ R matches a carriage return character. Equivalent to \x0d and \cm.The \s matches any whitespace character, including spaces, tabs, page breaks, and so on. equivalent to [\f\n\r\

For many technical engineers who need to work with text, you must have a thorough understanding of Python regular expressions, not only to understand what a Python regular expression is, but also to know about Python regular expression characters.In

Six, package and module1 module Python中每一个.py脚本定义一个模块，所以我们可以在一个.py脚本中定义一个实现某个功能的函数或者脚本，这样其他的.py脚本就可以调用这个模块了。调用的方式有三种，如下：[Python] View plain copyView code slices to my Code slice################################### # # Package and Module # # # # #

1. Regular expression Syntax:． Represents any character[] to match a specified character category, the so-called character category is a character set that you want to match, a relationship that can be understood as a character in a character set.^

PHP preg_replace () Regular replacement, unlike JavaScript regular substitution, PHP preg_replace () is the default is to replace all symbol matching conditions of the elements need our program processing data is not always pre-designed database

Basic knowledge of regular expressions:\ marks the next character as a special character, or a literal character, or a backward reference, or an octal escape character.For example, ' n ' matches the character "n". ' \ n ' matches a line break. The

1. CSS pseudo-elements are used to set special effects on certain selectors (used as a thing, similar to an element, but not an element).①:frist-line pseudo-element: used to set a special style to the first line of text, but only for block-level

The regular expression of JSWhether the checksum is all made up of numbersCodefunction IsDigit (s){var patrn=/^[0-9]{1,20}$/;if (!patrn.exec (s)) return falsereturn True}Check login name: Only 5-20 entries begin with a letter, can be numbered, "_", "

JavaScript is an interpretive programming language, mainly to enhance the dynamic effect of HTML pages JavaScript is made up of three parts: ECMAScript, BOM, DOM Single-line comment//multi-line/* */ Introduce the way to introduce

Regular expression parsing in JavaScriptA regular expression is an object that describes a character pattern, and JavaScript's RegExp objects and string objects define methods that use regular expressions to perform powerful pattern matching and

The first comparison system of learning regular expressions, this article in the PHP language as an example to learn.Basic conceptsRegular expressions = Ordinary characters (such as A-Z) + delimiters ( forward slash (/), hash sign (#), and Inverse (~

A Brief introduction:In essence, a regular expression (or RE) is a small, highly specialized programming language,(in Python) it is embedded in Python and is implemented through the RE module. The regular expression pattern isCompiled into a

Regular expressionsThe essence of the regular expression1, the essence of the regular expression (or RE) is a small, highly specialized programming language, (in Python) it is embedded in Python, and through the RE module implementation. The regular

Tag: expression returns the specified any regular module digital print classRe module \ Regular expression one, meta-character1,. ^ $ * + ? { } [ ] | ( ) \"."　　Represents (any one character) "*" for (any number of arbitrary characters, 0-Infinity) "+

1PHP2 /*3 non-printable characters4 \c----{4E00--9FA5} \x----{a-za-z}5 \f----Match a page break6 \ n----match a line break7 \ r----Match a carriage return line8 \s----matches any whitespace character, including spaces, tabs, page breaks9