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@ -9,7 +9,7 @@ Although, there's a bit of confusion, because there are many classes. To name a
Binary data in JavaScript is implemented in a non-standard way, compared to other languages. But when we sort things out, everything becomes fairly simple.
**The basic binary object is `ArrayBuffer` -- a reference to a fixed-length contiguos memory area.**
**The basic binary object is `ArrayBuffer` -- a reference to a fixed-length contiguous memory area.**
We create it like this:
```js run
@ -209,7 +209,7 @@ These methods allow us to copy typed arrays, mix them, create new arrays from ex
[DataView](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView) is a special super-flexible "untyped" view over `ArrayBuffer`. It allows to access the data on any offset in any format.
- For typed arrays, the constructor dictates what the format is. The whole array is supposed to be uniform. The i-th number is `arr[i]`.
- With `DataView` we access the data with methods like `.getUint8(i)` or `.gteUint16(i)`. We choose the format at method call time instead of the construction time.
- With `DataView` we access the data with methods like `.getUint8(i)` or `.getUint16(i)`. We choose the format at method call time instead of the construction time.
The syntax:
@ -249,7 +249,7 @@ dataView.setUint32(0, 0); // set 4-byte number to zero
To do almost any operation on `ArrayBuffer`, we need a view.
- It can be a `TypedArray`:
- `Uint8Array`, `Uint16Array`, `Uint32Array` -- for integer numbers of 8, 16 and 32 bits.
- `Uint8Array`, `Uint16Array`, `Uint32Array` -- for unsigned integers of 8, 16, and 32 bits.
- `Uint8ClampedArray` -- for 8-bit integers, "clamps" them on assignment.
- `Int8Array`, `Int16Array`, `Int32Array` -- for signed integer numbers (can be negative).
- `Float32Array`, `Float64Array` -- for signed floating-point numbers of 32 and 64 bits.
@ -261,7 +261,7 @@ There are also two additional terms:
- `ArrayBufferView` is an umbrella term for all these kinds of views.
- `BufferSource` is an umbrella term for `ArrayBuffer` or `ArrayBufferView`.
These are used in descriptions of methods that operate on binary data. `BufferSource` is one of the most common teerms, as it means "any kind of binary data" -- an `ArrayBuffer` or a view over it.
These are used in descriptions of methods that operate on binary data. `BufferSource` is one of the most common terms, as it means "any kind of binary data" -- an `ArrayBuffer` or a view over it.
Here's a cheatsheet: