Buffers: Node.js

Simple Guide to Buffers in Node.js

A Buffer in Node.js is used to handle raw binary data, which is useful when working with streams, files, or network data.

How to Create Buffers

1. From a String:

   const buf = Buffer.from('Hello');

1. Allocate a Buffer with a specific size:

   const buf = Buffer.alloc(10); // 10-byte buffer filled with zeros

1. From an Array of bytes:

   const buf = Buffer.from([72, 101, 108, 108, 111]); // Represents 'Hello'

Important Buffer Functions

1. Convert Buffer to String:

   const buf = Buffer.from('Hello');
   console.log(buf.toString()); // 'Hello'

1. Get Buffer Length:

   const buf = Buffer.from('Hello');
   console.log(buf.length); // 5 (each character takes 1 byte)

1. Write Data to Buffer:

   const buf = Buffer.alloc(5);
   buf.write('Hi');
   console.log(buf.toString()); // 'Hi'

1. Slice a Buffer:

   const buf = Buffer.from('Hello World');
   const slice = buf.slice(0, 5);
   console.log(slice.toString()); // 'Hello'

1. Copy from One Buffer to Another:

   const buf1 = Buffer.from('Hello');
   const buf2 = Buffer.alloc(5);
   buf1.copy(buf2);
   console.log(buf2.toString()); // 'Hello'

1. Compare Two Buffers:

   const buf1 = Buffer.from('abc');
   const buf2 = Buffer.from('abc');
   console.log(buf1.equals(buf2)); // true

1. Concatenate Multiple Buffers:

   const buf1 = Buffer.from('Hello');
   const buf2 = Buffer.from(' World');
   const buf3 = Buffer.concat([buf1, buf2]);
   console.log(buf3.toString()); // 'Hello World'

These are the key Buffer functions you need to know to start working with binary data in Node.js:

• Create, write, and read Buffers
• Slice, copy, compare, and concatenate Buffers

This is enough to handle most beginner use cases in Node.js!

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