سلام دوستان روزتون به خیر.
خیلی دقیق نتونستم کلمه کلیدی with رو درک کنم اکر امکانش هست توضیح بدید ممنون میشم.
این یک نمونه مثال
>>> with open(’/tmp/workfile’, ‘r’) as f:
… read_data = f.read()
یک توضیحات انگلیسی هم داخلش پیدا کردم. که اینو نوشته بود . راجب enter و exit توضیح داده . ولی من متوجه نمیشم
with
with statement is used to wrap the execution of a block of code within methods defined by the context manager.
Context manager is a class that implements __enter__ and __exit__ methods. Use of with statement ensures that the __exit__ method is called at the end of the nested block. This concept is similar to the use of try…finally block. Here, is an example.
with open('example.txt', 'w') as my_file:
my_file.write('Hello world!')
This example writes the text Hello world! to the file example.txt . File objects have __enter__ and __exit__ method defined within them, so they act as their own context manager.
First the __enter__ method is called, then the code within with statement is executed and finally the __exit__ method is called. __exit__ method is called even if there is an error. It basically closes the file stream.