C # Second article--about regular expressions in C #

In C #, a regular expression is a tool used to query certain characters or numbers in a string of characters given. Similar to the search function in office software, you can find it with precision or with a fuzzy look.

Metacharacters

Metacharacters	Description
.	Match any character other than line break
\b	Match the beginning or end of a word
\d	Match numbers
\s	Match any of the whitespace characters
\w	Match letters or numbers or underscores or kanji
^	Match the start of a string
$	Match the end of a string

Qualifier:

Qualifier	Description
*	Repeat 0 or more times
+	Repeat one or more times
?	Repeat 0 or one time
N	Repeat n times
{N,}	Repeat N or more times
{N,m}	Repeat N to M times

Assertion:

Assertion syntax	Description
(? =pattern)	Forward positive assertion that matches the position in front of the pattern
(?! Pattern	Forward negative assertion that matches a position not followed by pattern
(? <=pattern)	Back-to-positive assertion that matches the position behind the pattern
(? <!pattern)	Back to negative assertion, matching the position of the previous not pattern

C # Second article--about regular expressions in C #