Buffer is a temporary memory storage which stores the data when it is being moved from one place to another. Its like the array of integers.
The Buffer.fill() Method puts the data into the buffer instance. If the offset and end value are not given then the complete buffer will be filled.
Syntax:
buffer.fill( string, offset, end, encoding )
Parameters: This method accept four parameters as mentioned above and described below:
- string: It holds the data you need to put into the buffer.
- start: The index from which you need to start filling the buffer. Its default value is 0.
- end: The index till which you need to fill the buffer. The default value is buffer.length
- encoding: The encoding for data if data is in string format. The default value is utf8.
Return Value: This method returns a buffer object containing the values.
Below examples illustrate the use of Buffer.fill() method in Node.js:
Example 1:
// Node.js program to demonstrate the // Buffer.fill() Method // Allocating the space to buffer instance var buffer = Buffer.alloc(13); buffer.fill( 'GeeksforGeeks' ); console.log(buffer.toString()); |
Output:
GeeksforGeeks
Example 2:
// Node.js program to demonstrate the // Buffer.fill() Method // Allocating the space to buffer instance var buffer = Buffer.alloc(7); buffer.fill( 'geek' , 3); // Prints : ' geek' as we are starting // from index 3 to fill the buffer console.log(buffer.toString()); |
Output:
geek
Note: The above program will compile and run by using the node index.js
command.
Reference: https://nodejs.org/api/buffer.html#buffer_buf_fill_value_offset_end_encoding