Node.js Buffer.writeInt16BE() Method

The Buffer.writeInt16BE() method is an inbuilt application programming interface of class Buffer within Buffer module which is used to write integer value to buffer at the specified offset with the big-endian format. Integer value should be a valid signed 16-bit integer. Error is thrown if the value is outside the range of signed 16-bit integer. The integer value is interpreted and written as a two’s complement signed integer.

Syntax:

Buffer.writeInt16BE( value, offset )

Parameters: This method accept two parameters as mentioned above and described below:

• value: It is a 16-bit signed integer that has to be written into the buffer.
• offset: It is an integer value i.e. number of bytes to skip before starting to write into the buffer. The value of offset lies 0 to buf.length-2. It is optional parameter and its default value is 0.

Return Value: It returns an integer value that is the sum of offset plus the number of bytes written.

Below examples illustrate the use of buf.writeInt16BE() method in Node.js:

Example 1:

// Node.js program to demonstrate the
// Buffer.writeInt16BE() Method

// Allocate a buffer
const buf = Buffer.allocUnsafe(2);

// Writing the value to the buffer
buf.writeInt16BE(0x7bca);

// Display the buffer value
console.log(buf);

Output:

<Buffer 7b ca>

Example 2:

// Node.js program to demonstrate the
// Buffer.writeInt16BE() Method

// Allocate a buffer
const buf = Buffer.allocUnsafe(4);

// Writing the value to the buffer
// from 0 offset
buf.writeInt16BE(0x7bca, 0);

// Writing the value to the buffer
// from 2 offset
buf.writeInt16BE(0x7fff, 2);

// Display the result
console.log(buf);

Output:

<Buffer 7b ca 7f ff>

Example 3:

// Node.js program to demonstrate the
// Buffer.writeInt16BE() Method

// Allocate a buffer
const buf = Buffer.allocUnsafe(4);

// Writing the value to the buffer
// from 0 offset
buf.writeInt16BE(0x7bca, 0);

// Writing the value to the buffer
// from 2 offset
buf.writeInt16BE(0x7fff, 3);

// Display the result
console.log(buf);

Output:

internal/buffer.js:72
  throw new ERR_OUT_OF_RANGE(type || 'offset',
  ^
RangeError [ERR_OUT_OF_RANGE]: The value of "offset" is out of range.
It must be >= 0 and 
Reference: https://nodejs.org/api/buffer.html#buffer_buf_writeint16be_value_offset