Creating buffers in Node.js - Quick Revision & Summary

Recall & Review

beginner

What is a Buffer in Node.js?

A Buffer is a special object in Node.js used to store raw binary data. It helps handle data like files or network streams efficiently.

beginner

How do you create a Buffer from a string in Node.js?

Use Buffer.from('your string') to create a buffer containing the bytes of the string.

beginner

What does Buffer.alloc(size) do?

It creates a new Buffer of the given size in bytes, filled with zeros. Useful when you need a fixed-size buffer.

intermediate

Why should you avoid using Buffer(size) constructor in modern Node.js?

Because it creates uninitialized memory which can contain old data. Use Buffer.alloc(size) for safety.

beginner

How can you create a Buffer from an array of bytes?

Use Buffer.from([byte1, byte2, ...]) to create a buffer containing those bytes.

Which method creates a zero-filled Buffer of a specific size?

A Buffer.create(size)

B Buffer.from(size)

C Buffer.alloc(size)

D Buffer.new(size)

Buffer.alloc(size) creates a Buffer filled with zeros. Buffer.from expects data, not size.

How do you create a Buffer from the string 'hello'?

A Buffer.from('hello')

B new Buffer('hello')

C Buffer.alloc('hello')

D Buffer.create('hello')

Buffer.from('hello') creates a Buffer containing the bytes of the string 'hello'.

Why is using Buffer(size) constructor discouraged?

A It is slower than Buffer.alloc

B It creates uninitialized memory which may contain sensitive data

C It does not create a Buffer

D It only works with strings

Buffer(size) creates uninitialized memory which can contain old data, risking security.

Which of these creates a Buffer from an array of bytes [1, 2, 3]?

A Buffer.from([1,2,3])

B Buffer.alloc([1,2,3])

C Buffer.new([1,2,3])

D Buffer.create([1,2,3])

Buffer.from(array) creates a Buffer containing the bytes from the array.

What type of data does a Buffer store?

A Only numbers

B Text only

C JavaScript objects

D Raw binary data

Buffers store raw binary data, useful for files, network data, and more.

Explain how to create a Buffer from a string and why it might be useful.

Think about turning text into bytes for processing.

Describe the difference between Buffer.alloc(size) and Buffer(size) and why one is preferred.

Consider memory safety and old data exposure.