The count method is used to retrieve the number of occurrences of the specified string in another string . If the retrieved string does not exist, it returns 0, otherwise it returns the number of occurrences.
The syntax of the count method is as follows:
str.count(sub[,start[,end]])
1
In this method, the specific meaning of each parameter is as follows:
str : represents the original string;
sub : Indicates the string to be retrieved;
start : Specify the starting position of the retrieval, that is, where to start the detection. If not specified, the search starts from the beginning by default ;
end : Specify the end position of the search, if not specified, it means to search all the way to the end .
【Example 1】
Retrieves the number of occurrences of "." in the string "c.biancheng.net".
>>> str = "c.biancheng.net"
>>> str.count('.')
2
1
2
3
[Example 2]
>>> str = "c.biancheng.net"
>>> str.count('.',1)
2
>>> str.count('.',2)
1
1
2
3
4
5
As mentioned above, the search value corresponding to each character in the string starts from 0. Therefore, in this example, the search value 1 corresponds to the second character '.'. It can be analyzed from the output result that the search starts from the specified index position , which also contains this index location .
[Example 3]
>>> str = "c.biancheng.net"
>>> str.count('.',2,-3)
1
>>> str.count('.',2,-4)
0
