Node.js Buffer Module
Example
Convert the string "abc" into a stream of binary data:
var buf = Buffer.from('abc');
console.log(buf);
Run example »
Definition and Usage
The buffers module provides a way of handling streams of binary data.
The Buffer object is a global object in Node.js, and it is not necessary to
import it using the require keyword.
Syntax
The syntax for creating an empty Buffer of the length 15:
var buf = Buffer.alloc(15);
Buffer Properties and Methods
| Method | Description |
|---|---|
| alloc() | Creates a Buffer object of the specified length |
| allocUnsafe() | Creates a non-zero-filled Buffer of the specified length |
| allocUnsafeSlow | Creates a non-zero-filled and non-pooled Buffer of the specified length |
| byteLength() | Returns the numbers of bytes in a specified object |
| compare() | Compares two Buffer objects |
| concat() | Concatenates an array of Buffer objects into one Buffer object |
| copy() | Copies the specified number of bytes of a Buffer object |
| entries() | Returns an iterator of "index" "byte" pairs of a Buffer object |
| equals() | Compares two Buffer objects, and returns true if it is a match, otherwise false |
| fill() | Fills a Buffer object with the specified values |
| from() | Creates a Buffer object from an object (string/array/buffer) |
| includes() | Checks if the Buffer object contains the specified value. Returns true if there is a match, otherwise false |
| indexOf() | Checks if the Buffer object contains the specified value. Returns the first occurrence, otherwise -1 |
| isBuffer() | Checks if an object is a Buffer object |
| isEncoding() | Checks if the Buffer object supports the specified encoding |
| keys() | Returns an array of keys in a Buffer object |
| lastIndexOf() | Checks if the Buffer object contains the specified value. Returns the first occurrence, starting from the end, otherwise -1 |
| length | Returns the length of a Buffer object, in bytes |
| poolSize | Sets or returns the number of bytes used for pooling |
| readDoubleBE() | Reads a 64 bit double from a Buffer object, returns the result in big endian |
| readDoubleLE() | Reads a 64 bit double from a Buffer object, returns the result in little endian |
| readFloatBE() | Reads a 32 bit float from a Buffer object, returns the result in big endian |
| readFloatLE() | Reads a 32 bit float from a Buffer object, returns the result in little endian |
| readInt8() | Reads a 8 bit integer from a Buffer object |
| readInt16BE() | Reads a 16 bit integer from a Buffer object, returns the result in big endian |
| readInt16LE() | Reads a 16 bit integer from a Buffer object, returns the result in little endian |
| readInt32BE() | Reads a 32 bit integer from a Buffer object, returns the result in big endian |
| readInt32LE() | Reads a 32 bit integer from a Buffer object, returns the result in little endian |
| readIntBE() | Reads the specified number of bytes from a Buffer object, returns the result in big endian |
| readIntLE() | Reads the specified number of bytes from a Buffer object, returns the result in little endian |
| readUInt8() | Reads an unsigned 8 bit integer from a Buffer object |
| readUInt16BE() | Reads an unsigned 16 bit integer from a Buffer object, returns the result in big endian |
| readUInt16LE() | Reads an unsigned 16 bit integer from a Buffer object, returns the result in little endian |
| readUInt32BE() | Reads an unsigned 32 bit integer from a Buffer object, returns the result in big endian |
| readUInt32LE() | Reads an unsigned 32 bit integer from a Buffer object, returns the result in little endian |
| readUintBE() | Reads the specified number of bytes from a Buffer object, returns the result as an unsigned integer |
| readUIntLE() | Reads the specified number of bytes from a Buffer object, returns the result as an unsigned integer |
| slice() | Slices a Buffer object into a new Buffer objects starting and ending at the specified positions |
| swap16() | Swaps the byte-order of a 16 bit Buffer object |
| swap32() | Swaps the byte-order of a 32 bit Buffer object |
| swap64() | Swaps the byte-order of a 64 bit Buffer object |
| toString() | Returns a string version of a Buffer object |
| toJSON() | Returns a JSON version of a Buffer object |
| values() | Returns an array of values in a Buffer object |
| write() | Writes a specified string to a Buffer object |
| writeDoubleBE() | Writes the specified bytes, using big endian, to a Buffer object. The bytes should be 64 bit double. |
| writeDoubleLE() | Writes the specified bytes, using little endian, to a Buffer object. The bytes should be 64 bit double. |
| writeFloatBE() | Writes the specified bytes, using big endian, to a Buffer object. The bytes should be 32 bit float. |
| writeFloatLE() | Writes the specified bytes, using little endian, to a Buffer object. The bytes should be 32 bit float. |
| writeInt8() | Writes the specified bytes to a Buffer object. The bytes should be 8 bit integer |
| writeInt16BE() | Writes the specified bytes, using big endian, to a Buffer object. The bytes should be 16 bit integer. |
| writeInt16LE() | Writes the specified bytes, using little endian, to a Buffer object. The bytes should be 16 bit integer. |
| writeInt32BE() | Writes the specified bytes, using big endian, to a Buffer object. The bytes should be 32 bit integer. |
| writeInt32LE() | Writes the specified bytes, using little endian, to a Buffer object. The bytes should be 32 bit integer. |
| writeIntBE() | Writes the specified bytes, using big endian, to a Buffer object. |
| writeIntLE() | Writes the specified bytes, using little endian, to a Buffer object. |
| writeUInt8() | Writes the specified bytes to a Buffer object. The bytes should be 8 bit unsigned integer |
| writeUInt16BE() | Writes the specified bytes, using big endian, to a Buffer object. The bytes should be 16 bit unsigned integer. |
| writeUInt16LE() | Writes the specified bytes, using little endian, to a Buffer object. The bytes should be 16 bit unsigned integer. |
| writeUInt32BE() | Writes the specified bytes, using big endian, to a Buffer object. The bytes should be 32 bit unsigned integer. |
| writeUInt32LE() | Writes the specified bytes, using little endian, to a Buffer object. The bytes should be 32 bit unsigned integer. |
| writeUIntBE() | Writes the specified bytes, using big endian, to a Buffer object |
| writeUIntLE() | Writes the specified bytes, using little endian, to a Buffer object |
