---
title: "JSObjectGetArrayBufferByteLength(_:_:_:)"
framework: javascriptcore
role: symbol
role_heading: Function
path: "javascriptcore/jsobjectgetarraybufferbytelength(_:_:_:)"
---

# JSObjectGetArrayBufferByteLength(_:_:_:)

Returns the number of bytes in a JavaScript data object.

## Declaration

```swift
func JSObjectGetArrayBufferByteLength(_ ctx: JSContextRef!, _ object: JSObjectRef!, _ exception: UnsafeMutablePointer<JSValueRef?>!) -> Int
```

## Parameters

- `ctx`: The execution context to use.
- `object`: The JavaScript array buffer object with the length in bytes to return.
- `exception`: A pointer to a doc://com.apple.javascriptcore/documentation/JavaScriptCore/JSValueRef to store an exception in, if any. Pass NULL to discard any exception.

## Return Value

Return Value The number of bytes in the data object.

## See Also

### Working with Array Buffers

- [JSObjectMakeArrayBufferWithBytesNoCopy(_:_:_:_:_:_:)](javascriptcore/jsobjectmakearraybufferwithbytesnocopy(_:_:_:_:_:_:).md)
- [JSObjectGetArrayBufferBytesPtr(_:_:_:)](javascriptcore/jsobjectgetarraybufferbytesptr(_:_:_:).md)