How to check if a variable is None in Python
In this post we will give you information about How to check if a variable is None in Python. Hear we will give you detail about How to check if a variable is None in PythonAnd how to use it also give you demo for it if it is necessary.
we are going to learn about how to check if a variable is None or not in Python with the help of examples.
Note: None means null value in Python.
Consider, that we have the following variable in our code:
x = None
Now, we need to check if the above variable is None or not.
Change default configuration name of Laravel's created_at and updated_at
In this post we will give you information about Change default configuration name of Laravel's created_at and updated_at. Hear we will give you detail about Change default configuration name of Laravel's created_at and updated_atAnd how to use it also give you demo for it if it is necessary.
In this Laravel PHP Tutorial, I will let you know the use of created_at and updated_at column in a database table.
By default, Eloquent automatically maintain the date time value in created_at and updated_at column on your database table. If you do not want for eloquent to maintain created_at and updated_at columns then disable it by adding following property in your model class :
- class Member extends Eloquent {
- protected $table='members';
- public $timestamps= false;
- }
class Member extends Eloquent {
protected $table = 'members';
public $timestamps = false;
}If you want to map Laravel's timestamp from created_at to created_on and updated_at to modified_on then you can override const on your model in following way :
const CREATED_AT = 'created_on'; const UPDATED_AT = 'modified_on';
Now Eloquent will take care of the column "created_on" and "modified_on" on your database table.
How to disable created_at and updated_at timestamps in Laravel Model?
Label :
PHP Laravel PHP Framework How To MVC Web DevelopmentHope this code and post will helped you for implement Change default configuration name of Laravel's created_at and updated_at. if you need any help or any feedback give it in comment section or you have good idea about this post you can give it comment section. Your comment will help us for help you more and improve us. we will give you this type of more interesting post in featured also so, For more interesting post and code Keep reading our blogs
Using is keyword
To check if a variable is None or not, we can use the is keyword in Python.
The is keyword returns True, if the both values refers to the same object. Otherwise, it returns false.
Here is an example:
x = Noneif x is None: print('Variable is None')else: print('Variable is not None')Output:
'Variable is None'
In the above code,
We have first initialized a variable with a None value.
Then we used is keyword to check if both values refers to same object.
If it returns True it prints the variable is None, if variable is not None then it returns False and prints Variable is not None.
Other example:
y = 10if y is None: print('Variable is None')else: print('Variable is not None')Output:
'Variable is not None'
Similarly, we can also use the isinstance() function in Python to check if a given variable is None.
x = Noneif isinstance(x, type(None)): print('Variable is None')else: print('Variable is not None')The isinstance() function takes the two arguments, the first argument is object, and the second argument is type then It returns True if a given object is a specified type otherwise it returnsFalse.
Hope this code and post will helped you for implement How to check if a variable is None in Python. if you need any help or any feedback give it in comment section or you have good idea about this post you can give it comment section. Your comment will help us for help you more and improve us. we will give you this type of more interesting post in featured also so, For more interesting post and code Keep reading our blogs