swift - 如何为 Swift 3 更新 UnsafePointer 的数据声明？

Question

对于此声明，我收到以下错误:

 let data = Data(bytes: UnsafePointer<UInt8>(cubeData), count: cubeData.count * MemoryLayout<Float>.size)

cubeData 定义为:var cubeData = [Float](repeating: 0, count: size * size * size * 4)

错误:

 'init' is unavailable: use 'withMemoryRebound(to:capacity:_)' to temporarily view memory as another layout-compatible type.

我该如何解决这个问题？

谢谢!

Answer 1

你可以使用 Array.withUnsafeBufferPointer获取缓冲区指针(即指向具有其长度的数组的指针)。然后使用 Data.init(buffer:)从缓冲区指针启动数据。

let cubeData: [Float] = [1.1, 2.2, 3.3, 4.4]

let b = cubeData.withUnsafeBufferPointer { Data(buffer: $0) }

print(b as NSData)
// <cdcc8c3f cdcc0c40 33335340 cdcc8c40>