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ArrayBuffer

'To achieve maximum flexibility and efficiency, JavaScript typed arrays split the implementation into buffers and views. A buffer (implemented by the ArrayBuffer object) is an object representing a chunk of data; it has no format to speak of and offers no mechanism for accessing its contents. To access the memory contained in a buffer, you need to use a view. A view provides a context — that is, a data type, starting offset, and number of elements — that turns the data into an actual typed array.' – MDNThe ArrayBuffer has the following properties and methods:

.length

.isView(arg)

.transfer(oldBuffer [, newByteLength])

.prototype.byteLength

.prototype.slice()

.slice()


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<!DOCTYPE html><html><body><script>

ArrayBuffer.isView();                    // false
              ArrayBuffer.isView([]);                  // falseArrayBuffer.isView({});                  // falseArrayBuffer.isView(null);                // falseArrayBuffer.isView(undefined);           // falseArrayBuffer.isView(new ArrayBuffer(10)); // false ArrayBuffer.isView(new Uint8Array());    // trueArrayBuffer.isView(new Float32Array());  // trueArrayBuffer.isView(new Int8Array(10).subarray(0, 3));                                                                             // truevar buffer = new ArrayBuffer(2);var dv = new DataView(buffer);ArrayBuffer.isView(dv); // true

</script></body><html>

RESETRUNFULL
<!DOCTYPE html><html><body><script>

var buf1 = new ArrayBuffer(40);buf1.byteLength; // 40new Int32Array(buf1)[0] = 42;var buf2 = ArrayBuffer.transfer(buf1, 80);buf1.byteLength; // 0buf2.byteLength; // 80new Int32Array(buf2)[0]; // 42var buf3 = ArrayBuffer.transfer(buf2, 0);buf2.byteLength; // 0buf3.byteLength; // 0

</script></body><html>

RESETRUNFULL
<!DOCTYPE html><html><body><script>


   var buf1 = new ArrayBuffer(8);
   var buf2 = buf1.slice(0);
   var buf3 = buf1.slice(2,4);
   console.log(buf3.byteLength); // 2

</script></body><html>