Vim must learn well and understand the regular expression)

This article is well organized on the Internet, and its form is as follows:

Formal expression	Description and Examples	Unmatched strings
//	String containing the letter "A", such as "AB", "BAC", and "CBA"	"Xyz"
/./	A string containing the letter "A" and any subsequent characters, such as "AB" and "BAC" (use \.)	"A", "BA"
/^ XY/	A string starting with "XY", such as "XYZ" and "xyab" (use \ ^ To compare to ^)	"Callback", "bxy"
/XY $/	String ending with "XY", for example, a string ending with "XY", a string ending with "XY", for example, "Callback ", "abxy" (if you want to compare $, use \ $)	"Xya", "xyb"
[13579]	A string containing "1", "3", "5", "7", or "9", for example, "a3b" and "1xy"	"Y2K"
[0-9]	String containing numbers	String without data
A-z0-9	String containing numbers or letters	String without numbers and small numbers
A-zA-Z0-9	String containing numbers or letters	String without numbers and letters
B [aeiou] T	"Bat", "bet", "bit", "BOT", ""	"Bxt", "bzt"
[^ 0-9]	String without data (use \ ^ for comparison ^)	String containing numbers
[^ Aeiouaeiou]	A string without the mother tone (use \ ^ for comparison ^)	Audio-containing string
[^ \ ^]	It does not contain "^" strings, such as "XYZ" and "ABC"	"XY ^", "a ^ BC"

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Specific characters of the Regular Expression	Description	Equivalent positive expression
\ D	Data	[0-9]
\ D	Non-numeric characters	[^ 0-9]
\ W	Number, letter, base character	[A-zA-Z0-9 _]
\ W	Non \ W	[^ A-zA-Z0-9 _]
\ S	Blank character	[\ R \ t \ n \ F]
\ S	Non-blank characters	[^ \ R \ t \ n \ F]

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Formal expression	Description
/? /	Zero or one A (If yes? Character, use \?)
/A +/	One or more A (use \ + for comparison to + characters)
/*/	Zero or more A characters (use \ * If You Want To match * characters \*)
/A {4 }/	Four
/A {5, 10 }/	Five to ten
/A {5 ,}/	At least five
/A {, 3 }/	Up to three
/A. {5} B/	Five (non-linear) characters in A and B

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Character	Description	Simple Example
\	Escape special characters	/A \ */Applicable to comparison with "A *", where * is a special character. To avoid its special meaning, you must add "\"
^	The starting position of the primary Column	/^ A/comparable to "a" in "ABCD", but not comparable to "AAB"
$	Compare the end position of the limit Column	/A $/comparable to "a" in "BCDA", but not comparable to "AAB"
*	Zero or more times than the previous character	/Bo */comparable to "booo" in "good boook" or "B" in "good BK"
+	Equivalent to {1 ,}	/A +/comparable to "AAA" in "caaandy", but not comparable to "cndy"
?	Zero or one time than the previous character	/E? L/comparable to "EL" in "Angel", it can also be compared to "L" in "angle"
.	Compared to any character (but the Delimiter is not counted)	/. N/comparable to "an" and "on" in "Nay, an apple is on the tree", but not comparable to "nay"
(X)	Compare to X and store the matching part into a variable	/(A *) and (B *)/comparable to "AAA" and "BB" in "AAA and BB ", set the two pairs to Regexp. $1 and Regexp. $2.
XY	Comparison with X or Y	/A * B */g can compare "AAA" and "BB" in "AAA and BB"
{N}	Compared to the previous CHARACTER n times, n is a positive integer	/A {3}/comparable to "AAA" in "lllaaalaa", but not "AA"
{N ,}	Compared to the previous character for at least N times, n is a positive number	/A {3,}/comparable to "AAA" and "AAAA" in "aa aaa aaaa", but not "AA"
{N, m}	The ratio is positive for at least N times and at most m times for the previous character.	/A {3, 4}/comparable to "AAA" and "aaaa" in "aa aaa aaaaa", but not comparable to "AA" and "AAAAA"
[Xyz]	Compared to any character in the ARC	/[ECM]/comparable to "E", "C", or "M" in "welcome"
[^ XYZ]	Compared to any character that does not exist in the ARC	/[^ ECM]/the opposite of [xyz] for "W", "L", and "O" in "welcome. (Note the difference between the functions of/^/and [^] at the same time .)
[\ B]	Backspace character)	The difference between [\ B] and \ B can be better than that of a backspace.
\ B	Comparison with English text, such as spaces	For example,/\ bn \ W/can be compared to 'no' in "noonday '; /\ WY \ B/comparable to 'ly 'in "possibly yesterday'
\ B	Comparison with non-English text 」	For example,/\ W \ BN/can be compared to 'on' in "noonday ', In addition,/Y \ B \ W/can be compared to 'day' in "possibly yesterday'
\ CX	Control Character, where X is a control character	/\ Cm/can be compared to control-m in a string
\ D	Equivalent to [0-9]	/[\ D]/comparable to any number of words from "0" to "9", but their names, such as letters, are not comparable
\ D	Equivalent to [^ 0-9]	/[\ D]/comparable to "W" ""... However, it is not comparable to a number such as "7" and "1 ".
\ F	Comparison with form-feed	If there is a line in the text that produces "success", the comparison can be successful.
\ N	Comparison with the delimiter	If there is a line with "success" in the text, the comparison can be successful.
\ R	Returns
\ S	Equivalent to [\ f \ n \ r \ t \ v]	/\ S \ W */comparable to "B" in "a B"
\ S	For any non-blank character, it is equivalent to [^ \ f \ n \ r \ t \ v]	/\ S/\ W * is comparable to "a" in "a B"
\ T	Comparison Between Positioning characters (Tab)
\ V	Vertical Tab)
\ W	Equivalent to [A-Za-z0-9 _]	/\ W/comparable to ". _! "A", "_", and "9" in "9 ″.
\ W	Equivalent to [^ A-Za-z0-9 _]	/\ W/comparable to ". _! ".", "", "!" In 9 ", It can be seen that the function is opposite to/\ W.
\ OOctal	Comparison with the eight-in-one, of whichOctalIt is an octal number.	/\ Oocetal123/compares the character value corresponding to "123" in the ASCII code with the octal.
\ XHEX	Compare to the hexadecimal position, whereHEXIs the hexadecimal number	/\ Xhex38/can be equivalent to the character corresponding to "38" in the ASCII code that matches the hexadecimal value.