Python | Check if dictionary is empty
Sometimes, we need to check if a particular dictionary is empty or not. And this particular task has its application in web development domain in which we sometimes need to test for results of a particular query or check whether we have any key to add info into database. Let’s discuss certain ways in which this task can be performed.
Method #1 : Using bool()
The bool function can be used to perform this particular task. As name suggests it performs the task of converting an object to a boolean value, but here, passing an empty string returns a False, as failure to convert something that is empty.
# Python3 code to demonstrate# Check if dictionary is empty# using bool() # initializing empty dictionarytest_dict = {} # printing original dictionaryprint("The original dictionary : " + str(test_dict)) # using bool()# Check if dictionary is empty res = not bool(test_dict) # print resultprint("Is dictionary empty ? : " + str(res)) |
Output :
The original dictionary : {}
Is dictionary empty ? : True
Method #2 : Using not operator
This task can also be performed using the not operator that checks for a dictionary existence, this evaluates to True, if any key in the dictionary is not found.
# Python3 code to demonstrate# Check if dictionary is empty# using not operator # initializing empty dictionarytest_dict = {} # printing original dictionaryprint("The original dictionary : " + str(test_dict)) # using not operator# Check if dictionary is empty res = not test_dict # print resultprint("Is dictionary empty ? : " + str(res)) |
Output :
The original dictionary : {}
Is dictionary empty ? : True
Last Updated on November 11, 2021 by admin