How to solve problems with Python Regular Expression objects

Python Regular Expression objects have many problems in our use and need to be noticed. Next, let's take a look at how to apply Python Regular Expression objects to related technologies. Hope to help you.

Generation Method: Pass

 
 

  
  
Re. compile (pattern, [flags]) Back
  
  
Match (string [, pos [, endpos]); returns string [pos, endpos] matching
  
  
MatchObject of pattern
 
 

Python code

 
 

  
  
split( string[, maxsplit = 0])   
  
  
findall( string[, pos[, endpos]])   
  
  
sub( repl, string[, count = 0])  
 
 

These functions are the same as those in the re module, but the calling form is slightly different.

Re. Several Functions and several functions of the regular expression object have the same function, but if the same program
Using these functions multiple times, several functions of the regular expression object are more efficient.

Matchobject

Use re. match (......) And re. compile (......). Match return

This object has the following methods and attributes:

Method:

 
 

  
  
group( [group1, ...])   
  
  
groups( [default])   
  
  
groupdict( [default])   
  
  
start( [group])   
  
  
end( [group])  
 
 

The best way to illustrate these functions is to give an example.

 
 

  
  
matchObj = re.compile(r”(?P\d+)\.(\d*)”)   
  
  
m = matchObj.match(’3.14sss’)   
  
  
#m = re.match(r”(?P\d+)\.(\d*)”, ‘3.14sss’)   
  
  
print m.group()   
  
  
print m.group(0)   
  
  
print m.group(1)   
  
  
print m.group(2)   
  
  
print m.group(1,2)   
  
  
print m.group(0,1,2)   
  
  
print m.groups()   
  
  
print m.groupdict()   
  
  
print m.start(2)   
  
  
print m.string  
 
 

The output is as follows:

 
 

  
  
3.14   
  
  
3.14   
  
  
3   
  
  
14   
  
  
(’3′, ‘14′)   
  
  
(’3.14′, ‘3′, ‘14′)   
  
  
(’3′, ‘14′)   
  
  
{’int’: ‘3′}   
  
  
2   
  
  
3.14sss  
 
 

Therefore, group () and group (0) are returned, which match the string of the entire expression. In addition, group (I) is the regular expression that uses the '3. 14', '3', '14') can best illustrate the problem.