What is the Buffer.writeUIntLE() method in Node.js?
The Buffer.writeUIntLE() method in Node.js writes a given number of bytes at a specified offset from a buffer in the
Syntax
The Buffer.writeUIntLE() method can be declared as shown in the code snippet below:
Buffer.writeUIntLE(value, offset, byteCount)
Parameters
-
value: A 32 bit signed integer to be written in the buffer. -
offset: The offset determines the number of bytes to skip before reading the buffer. In other words, it is the index of the buffer.- The value of
offsetshould be range from0 to (bufferLength - byteCount). - The default value of
offsetis 0.
- The value of
-
byteCount: The number of bytes to be read.- The value of
byteCountshould range from0 to 6.
- The value of
Return value
The writeUIntLE() method returns an integer that offset + the number of bytes write to the buffer.
Code
The code snippet below demonstrates the use of the writeUIntLE() method:
const buff = Buffer.allocUnsafe(4);buff.writeUIntLE(0x12345678, 0, 4);console.log(buff);
Explanation
-
In line 1, we declare a buffer,
buff. -
The
writeUIntLE()method is used in line 3 to write 4 bytes from the index 0 in the little-endian format.As one index of the buffer is 8 bits, we need to write at 4 indices. The
writeUIntLE()method writes at 4 indices ofbuff, starting from the index0i.e.,index = 0-index + 4 = 4.Since the code is in the Little Endian format, index 4 is written before index 3, index 3 is written before index 2, and so on.