Typed arrays are used great for raw binary data. If you website streams video, audio, or transfers large amounts of data through sockets. Typed arrays make it quick and easy for JS code to manipulate binary data.
Don't confuse with a normal array. This isArray() method will return false and not all methods are avail such as push and pop.
Split into buffers and views. The buffer is an object representing the chunk of data and does not have mechanism to access it's contents. A view provides that context which is a data type and the number of elements. You can think of the view as turning the data into an actual array.
The types of array views follow all the usually numeric types. Int8, Unit32, Float64
| Type | Size in bytes | Description | Web IDL type | Equivalent C type |
|---|---|---|---|---|
| Int8Array | 1 | 8-bit two's complement signed integer | byte | int8_t |
| Uint8Array | 1 | 8-bit unsigned | integer octet | uint8_t |
| Uint8ClampedArray | 1 | 8-bit unsigned | integer (clamped) octet | uint8_t |
| Int16Array | 2 | 16-bit two's complement | signed integer short | int16_t |
| Uint16Array | 2 | 16-bit unsigned integer | unsigned short | uint16_t |
| Int32Array | 4 | 32-bit two's complement | signed integer long | int32_t |
| Uint32Array | 4 | 32-bit unsigned integer | unsigned long | uint32_t |
| Float32Array | 4 | 32-bit IEEE | floating point number unrestricted float | float |
| Float64Array | 8 | 64-bit IEEE | floating point number unrestricted double | double |
The first thing to do is to declare your buffer.
var buffer = new ArrayBuffer(16);
Next you need your typed typedArray to take in the buffer. Now we have a buffer assigned to a chunk of memory initialized to zero. To read and use this buffer we have to create a view.
var int32View = new Int32Array(buffer);
Now that we have a view into this data we can then act on it like a standard array.
for (var i = 0; i < int32View.length; i++) {
int32View[i] = i * 2;
}
This will fill out the 4 values of the allocated indices, 4 entries at 4 bytes each makes 16 total bytes