Python string processing function Big Summary

str= ' python String function '

Generate string variable str= ' python string function '

String length acquisition: Len (str)

Example: print '%s length=%d '% (Str,len (str))

1. Letter Handling

All caps: Str.upper ()

All lowercase: str.lower ()

Case swap: Str.swapcase ()

Initial capitalization, remaining lowercase: str.capitalize ()

Initial capital: Str.title ()

print '%s lower=%s '% (Str,str.lower ())

print '%s upper=%s '% (Str,str.upper ())

print '%s swapcase=%s '% (Str,str.swapcase ())

print '%s capitalize=%s '% (str,str.capitalize ())

print '%s title=%s '% (Str,str.title ())

2. Formatting related

Get fixed length, right alignment, left not enough space to be padded: str.ljust (width)

Get fixed length, left alignment, right not enough space to complement: str.ljust (width)

Get fixed length, middle alignment, not enough space on both sides: str.ljust (width)

Get fixed-length, right-aligned, left less than 0-padded

print '%s ljust=%s '% (Str,str.ljust (20))

print '%s rjust=%s '% (Str,str.rjust (20))

print '%s center=%s '% (Str,str.center (20))

print '%s zfill=%s '% (Str,str.zfill (20))

3. String Search Related

Search for specified string, no return -1:str.find (' t ')

Specify starting Position search: Str.find (' t ', start)

Specify start and end position search: Str.find (' t ', start,end)

Search from right: Str.rfind (' t ')

Number of specified strings searched: Str.count (' t ')

All of the above methods can be replaced with index, the difference is to use the index to find not to throw an exception, and find returns-1

print '%s find nono=%d '% (str,str.find (' Nono '))

print '%s find t=%d '% (str,str.find (' t '))

print '%s find t from%d=%d '% (str,1,str.find (' t ', 1))

print '%s find t from%d to%d=%d '% (str,1,2,str.find (' t ', $))

#print '%s index Nono '% (Str,str.index (' Nono ', up))

print '%s rfind t=%d '% (str,str.rfind (' t '))

print '%s Count t=%d '% (str,str.count (' t '))

4. String substitution related

Replace old to New:str.replace (' old ', ' new ')

Replace the specified number of times with old as New:str.replace (' old ', ' new ', maxreplacetimes)

print '%s replace T to *=%s '% (str,str.replace (' t ', ' * '))

print '%s replace T to *=%s '% (str,str.replace (' t ', ' * ', 1))

5. String to go to the space and go to the specified character

Go on both sides Space: Str.strip ()

Left space: Str.lstrip ()

Go right Space: Str.rstrip ()

Go to both sides of the string: Str.strip (' d '), corresponding to the Lstrip,rstrip

str= ' python String function '

print '%s strip=%s '% (Str,str.strip ())

str= ' python String function '

print '%s strip=%s '% (Str,str.strip (' d '))

6. Split string by specified character array: Str.split (")

By default, separated by spaces

Str= ' a b C de '

print '%s strip=%s '% (Str,str.split ())

Str= ' A-b-c-de '

print '%s strip=%s '% (str,str.split ('-'))

7. String Judgments Related

Whether to start with start: Str.startswith (' Start ')

End With end: Str.endswith (' End ')

Whether it is all letters or numbers: Str.isalnum ()

Full letter: Str.isalpha ()

Whether full number: Str.isdigit ()

Full lowercase: str.islower ()

All caps: Str.isupper ()

str= ' python String function '

print '%s startwith t=%s '% (str,str.startswith (' t '))

print '%s endwith d=%s '% (Str,str.endswith (' d '))

print '%s isalnum=%s '% (Str,str.isalnum ())

Str= ' Pythonstringfunction '

print '%s isalnum=%s '% (Str,str.isalnum ())

print '%s isalpha=%s '% (Str,str.isalpha ())

print '%s isupper=%s '% (Str,str.isupper ())

print '%s islower=%s '% (Str,str.islower ())

print '%s isdigit=%s '% (Str,str.isdigit ())

Str= ' 3423 '

print '%s isdigit=%s '% (Str,str.isdigit ())

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