快速转换:错误- UnsafeMutablePointer

Question

我正在尝试将我的Swift 2代码转换成最新的语法(Swift 3)。我收到以下错误：

不能使用类型的参数列表(UnsafeMutablePointer！)调用“UnsafeMutablePointer”类型的初始化程序。

Swift 2代码：

let rawData = UnsafeMutablePointer<CUnsignedChar>(calloc(height * width * 4, Int(sizeof(CUnsignedChar))))

有人能帮我解决这个转换语法问题吗？

Answer 1

calloc返回一个“原始指针”(相当于C中void *的Swift )。可以使用assumingMemoryBound将其转换为类型化指针。

let rawData = calloc(width * height, MemoryLayout<CUnsignedChar>.stride).assumingMemoryBound(to: CUnsignedChar.self)

交替使用allocate()方法的UnsafeMutablePointer

let rawData = UnsafeMutablePointer<CUnsignedChar>.allocate(capacity: width * height)
rawData.initialize(to: 0, count: width * height)
// ...

rawData.deinitialize()
rawData.deallocate(capacity: width * height)