Python bytearray() function

The Python bytearray() function returns a new array of bytes. It is a mutable sequence of integers in the range 0 <= x < 256. This function can convert a specified object into a bytearray object or it can create an empty bytearray object of the required size. It is one of the built-in functions in Python.

The byte array can be created from the following sources

• String We can create a bytearray from a string by encoding it to bytes using str.encode().

• Integer If the source is an integer, an array with null value of specified size will be created.

• Object In this case, a read-only buffer is used to initialize the byte array.

• Iterable Creates an array of size equal to the length of iterable.

• No source If no source is specified, a byte array of size 0 is created.

Syntax

Following is the syntax of the Python bytearray() function

bytearray(source)
or,
bytearray(source, encoding)
or,
bytearray(source, encoding, errors)

Parameters

The Python bytearray() function accepts three parameters, all of which are optional

• source It represents an object such as a list, string, or tuple.

• encoding It represents the encoding of the passed string.

• errors It specifies the required action when encoding fails.

Return Value

The Python bytearray() function returns a new array of bytes.

bytearray() function Examples

Practice the following examples to understand the use of bytearray() function in Python:

Example: Use of bytearray() Function

The following example shows the usage of Python bytearray() function. Here we are creating an empty bytearray.

empByte_array = bytearray()
print("It is an example of empty bytearray:", empByte_array)

When we run above program, it produces following result

It is an example of empty bytearray: bytearray(b'')

Example: Convert String to bytearray Object Using bytearray()

In the code below, we are converting a given string into array of bytes. To do so, we use bytearray() function by passing string and encoding as parameter values.

byte_arrayStr = "Tutorials Point bytearray"
str_byte_array = bytearray(byte_arrayStr, 'utf-8')
print("Creating bytearray from string:")
print(str_byte_array)

Following is an output of the above code

Creating bytearray from string:
bytearray(b'Tutorials Point bytearray')

Example: Create bytearray of Specified Size Using bytearray()

The code below demonstrates how to create a byte array of the specified size. We are going to pass the size and value as arguments to the bytearray() function.

size = 5
value = 1
new_byte_array = bytearray([value]*size)
print("Bytearray of the given size:")
print(new_byte_array)

Output of the above code is as follows

Bytearray of the given size:
bytearray(b'\x01\x01\x01\x01\x01')

Example: Modify bytearray

In the code below a bytearray is created using bytearray() function. Then we modify its 8th character using the ord() function. Since a bytearray object is mutable, it can be modified easily.

byte_arr = bytearray('Tuorialspoint', 'utf-8')
print("Original bytearray:", byte_arr)
byte_arr[8] = ord('P')
print("Modified bytearray:", byte_arr)

Following is an output of the above code

Original bytearray: bytearray(b'Tuorialspoint')
Modified bytearray: bytearray(b'TuorialsPoint')