find substring in string in python code example

Example 1: python find all elements of substring in string

def find_all(a_str, sub):
    start = 0
    while True:
        start = a_str.find(sub, start)
        if start == -1: return
        yield start
        start += len(sub) # use start += 1 to find overlapping matches

list(find_all('spam spam spam spam', 'spam')) # [0, 5, 10, 15]

Example 2: python get a substring of a string

>>> x = "Hello World!"
>>> x[2:]
'llo World!'
>>> x[:2]
'He'
>>> x[:-2]
'Hello Worl'
>>> x[-2:]
'd!'
>>> x[2:-2]
'llo Worl'

Example 3: how to check for a substring in python

def find_string(string,sub_string):
	return string.find(sub_string)
#.find() also accounts for multiple occurence of the substring in the given string