PythonString methods
str.
Returns the index of the first occurrence of a fragment, or -1.
- Returns
- The index of the first occurrence, or
-1. - Changes the original
- No
Example
#Python
email = "emma.smith@codeworlds.com"
at = email.find("@")
print(at)
print(email[:at])
print(email.find("#"))
print("codeworlds" in email)Resultsaved result, you can check it
10
emma.smith
-1
True
Definition and usage
#The find() method looks for a fragment in a string and returns the index of its first occurrence. If the fragment is not there, it returns -1 instead of raising an error.
The optional start and end arguments limit the search range. rfind() searches from the end and returns the index of the last occurrence.
To simply check whether a fragment is present, the in operator is clearer. The index() method works like find(), but raises ValueError when the fragment is missing.
Syntax
#Syntax
string.find(sub, start=0, end=len(string))Parameters
#sub
str
The fragment to search for.start
int, optional
The index to start searching from.end
int, optional
The index to stop searching at (exclusive).
Good practices
#- Use
into check whether a fragment is present. Savefind()for situations where you need the position. - Remember that
-1is a valid index in slices. Always check the result before using it to slice a string.
Related entries
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