python string common actions summary

String common operations

String Manipulation	Meaning Explanation
s=r'XXX'	R represents foregoing quoted strings without escaping
b、u	Quoted strings preceding band urepresent byte string and Unicode strings
s1 + s2	String splicing
s * 3	Repeat string
s[i]、s[i:j]	String indexing and slicing
only the (S)	Required length of the string
"abc %s" % d	String formatting expressions
ord()	Seeking the ASCII-character string
chr()	Returns the character corresponding to the ASCII code

Meaning escape character string list

Escape character	significance
\\	\
\'	'
\"	"
\a	Bell
\b	backspace
\f	Feed
\n	Wrap
\r	Enter
\t	Horizontal tab

String common method

1. find()Method: String lookup operation. Returns the position of the first substring

s = 'spam'
s.find('pa')   #返回1

2. replace()Method: replace the contents of the string

#replace用法：replace(old, new, [, count]) 其中count可以省略，表示从左往右替换几个子字符串
s.replace('pa', 'Pa')    #s = 'sPam'

3. split()Method: The delimiter string into substrings

line = 'aaa, bbb, ccc'
line.split(',')     #返回['aaa', 'bbb', 'ccc', 'ddd]
# 若split()内为空则默认以一个或多个空格为分隔符

Rookie Tutorial link: http://www.runoob.com/python/att-string-split.html

4. strip()Method: Remove the string t beginning and end of the specified character (the default is a space or a newline)

Derived: lstrip () The rstrip and () method respectively processed from left to right and right to left

Syntax: str.strip ([chars]) #chars: Specifies to delete characters

Rookie Tutorial link: http://www.runoob.com/python/att-string-rstrip.html

5. upper()Method: Lowercase letters are converted to upper case string

str.upper() #返回值为小写字母转为大写字母的字符串。

There are similar:

lower（） Convert uppercase letters to lowercase;

capitalize（） The string of letters capitalized rest lowercase

title() The first letter of each word in a string of letters uppercase lowercase rest

Related Links: blog Garden - Python in upper, lower, capitalize, title

6. join()Method: The list of objects and the like can be iterative in particular into a string delimiter

# example:
'.'.join(['a', 'b', 'c'])  # 输出:"a.b.c"

Tips: ** applies to only the above-described character string type in python, can be applied to various types of generic operations are in the form of built-in functions or expressions, such as len (x), x [0]; However, the particular type of operation is the form of method calls, such as str.upper ()