如何通过匹配python中的某些字符从字符串中删除一些字符

Question

i am trying to delete certain portion of a string if a match found in the string as below

string = 'Newyork, NY'

I want to delete all the characters after the comma from the string including comma , if comma is present in the string

Can anyone let me now how to do this .

Answer 1

Use .split() :

string = string.split(',', 1)[0]

We split the string on the comma once , to save python the work of splitting on more commas.

Alternatively, you can use .partition() :

string = string.partition(',')[0]

Demo:

>>> 'Newyork, NY'.split(',', 1)[0]
'Newyork'
>>> 'Newyork, NY'.partition(',')[0]
'Newyork'

.partition() is the faster method:

>>> import timeit
>>> timeit.timeit("'one, two'.split(',', 1)[0]")
0.52929401397705078
>>> timeit.timeit("'one, two'.partition(',')[0]")
0.26499605178833008

Answer 2

You can split the string with the delimiter "," :

string.split(",")[0]

Example:

'Newyork, NY'.split(",") # ['Newyork', ' NY']
'Newyork, NY'.split(",")[0] # 'Newyork'

Answer 3

Try this :

s = "this, is"
m = s.index(',')
l = s[:m]

Answer 4

A fwe options:

• string[:string.index(",")]

  This will raise a ValueError if , cannot be found in the string. Here, we find the position of the character with .index then use slicing.

• string.split(",")[0]

  The split function will give you a list of the substrings that were separated by , , and you just take the first element of the list. This will work even if , is not present in the string (as there'd be nothing to split in that case, we'd have string.split(...) == [string] )