Python bytearray() Function
Python3 Built-in Functionsbytearray()It is a built-in function in Python used to create mutable byte sequences.
bytearray is very similar to bytes, but with one key difference: bytearray is mutable, and its bytes can be modified at any time. This makes it very useful in scenarios where binary data needs to be modified frequently.
Word Definition： bytearrayIt means "byte array" and is a mutable byte sequence.
Basic Syntax and Parameters
Syntax Format
bytearray(source) bytearray(source, encoding) bytearray(source, encoding, errors)
Parameter Description
- Parameter source：
- Type: Integer, iterable object, string
- Description: Source data used to initialize the byte array.
Function Description
- Return Value: Returns a mutable bytearray object.
- Features: The byte elements within it can be modified.
Examples
Example 1: Creating bytearray
Example
# Create a bytearray of specified length
b = bytearray(5)
print(b) # Output: bytearray(b'\x00\x00\x00\x00\x00')
# Create from an iterable object
b = bytearray([72, 101, 108, 108, 111])
print(b) # Output: bytearray(b'Hello')
# Create from a string
b = bytearray(Hello, encoding='utf-8')
print(b) # Output: bytearray(b'\xe4\xbd\xa0\xe5\xa5\xbd')
# Empty bytearray
b = bytearray()
print(b) # Output: bytearray(b'')
b = bytearray(5)
print(b) # Output: bytearray(b'\x00\x00\x00\x00\x00')
# Create from an iterable object
b = bytearray([72, 101, 108, 108, 111])
print(b) # Output: bytearray(b'Hello')
# Create from a string
b = bytearray(Hello, encoding='utf-8')
print(b) # Output: bytearray(b'\xe4\xbd\xa0\xe5\xa5\xbd')
# Empty bytearray
b = bytearray()
print(b) # Output: bytearray(b'')
Expected output:
bytearray(b'\x00\x00\x00\x00\x00') bytearray(b'Hello') bytearray(b'\xe4\xbd\xa0\xe5\xa5\xbd') bytearray(b'')
Code analysis:
- The creation method is similar to bytes.
- bytearray can be initialized in multiple ways.
Example 2: Modifying bytearray
Example
# bytearray is mutable
b = bytearray("Hello", encoding='utf-8')
print(b) # Output: bytearray(b'Hello')
# Modify a single byte
b[0] = 74 # ASCII code of 'J'
print(b) # Output: bytearray(b'Jello')
# Append byte
b.append(33) # ASCII code of '!'
print(b) # Output: bytearray(b'Jello!')
# Extend
b.extend([33, 33])
print(b) # Output: bytearray(b'Jello!!!')
# Delete
del b[0]
print(b) # Output: bytearray(b'ello!!!')
b = bytearray("Hello", encoding='utf-8')
print(b) # Output: bytearray(b'Hello')
# Modify a single byte
b[0] = 74 # ASCII code of 'J'
print(b) # Output: bytearray(b'Jello')
# Append byte
b.append(33) # ASCII code of '!'
print(b) # Output: bytearray(b'Jello!')
# Extend
b.extend([33, 33])
print(b) # Output: bytearray(b'Jello!!!')
# Delete
del b[0]
print(b) # Output: bytearray(b'ello!!!')
Expected output:
bytearray(b'Hello') bytearray(b'Jello') bytearray(b'Jello!') bytearray(b'Jello!!!') bytearray(b'ello!!!')
bytearray supports a rich set of modification operations: index assignment, append, extend, del, etc.
Other Extensions