The built-in function memoryview() is used to return the memory view object of the given object. A memory view is a better way to expose the buffer protocol in Python. By creating a memory view object, it allows you to access the internal buffers of an object.The buffer protocol helps to access the internal data of an object, internal data may be a memory array or a buffer.
memoryview(obj) # Where obj can be a byte or bytearray
Takes only one parameter.Here the obj will support the buffer protocol (bytes, bytearray).
| Parameter | Description | Required / Optional |
|---|---|---|
| obj | an object whose internal data is to be exposed | Required |
We can also update the object in memory view.
| Input | Return Value |
|---|---|
| obj | memory view object |
#random bytearray
random_byte_array = bytearray('ABC', 'utf-8')
mv = memoryview(random_byte_array)
# access memory view's zeroth index
print(mv[0])
# create byte from memory view
print(bytes(mv[0:2]))
# create list from memory view
print(list(mv[0:3]))
Output:
65 b'AB' [65, 66, 67]
# random bytearray
random_byte_array = bytearray('ABC', 'utf-8')
print('Before updation:', random_byte_array)
mv = memoryview(random_byte_array)
# update 1st index of mv to Z
mv[1] = 90
print('After updation:', random_byte_array)
Output:
Before updation: bytearray(b'ABC') After updation: bytearray(b'AZC')
barr = bytearray('Python','utf-8')
mv = memoryview(barr)
print(type(mv))
mv[0] = 65
print(barr)
Output:
bytearray(b'Aython')
