Python3 Dictionary in Operator
Python3 DictionaryDescription
Python DictionaryinThe in operator is used to determine whether a key exists in the dictionary. If the key is in the dictionary dict, it returns true, otherwise it returns false.
andnot inThe not in operator is exactly the opposite. If the key is in the dictionary dict, it returns false, otherwise it returns true.
Syntax
Syntax of the in operator:
key in dict
Parameters
- key -- The key to search for in the dictionary.
Return Value
Returns true if the key is in the dictionary, otherwise returns false.
Examples
The following example demonstrates how to use the in operator with dictionaries:
Example (Python 3.0+)
#!/usr/bin/python3
thisdict = {'Name': 'Example', 'Age': 7}
# Check whether key Age exists
if 'Age' in thisdict:
print("Key Age exists")
else :
print("Key Age does not exist")
# Check whether key Sex exists
if 'Sex' in thisdict:
print("Key Sex exists")
else :
print("Key Sex does not exist")
# not in
# Check whether key Age does not exist
if 'Age' not in thisdict:
print("Key Age does not exist")
else :
print("Key Age exists")
The output of the above example is:
键 Age 存在 键 Sex 不存在 键 Age 存在
Other Extensions