arrays - swift 错误 : Cannot convert value of type 'ArraySlice' to expected argument type

Question

我遇到了这个错误，我是 Swift 的新手。我想获取 >= 5 的数组的最后 5 个点，并将这 5 个点作为数组参数传递给函数。我怎样才能做到这一点并克服这个错误？

无法将“ArraySlice”类型的值转换为预期的参数类型“[CGPoint]”

if (self.points?.count >= 5) {
    let lastFivePoints = self.points![(self.points!.count-5)..<self.points!.count]
    let angle = VectorCalculator.angleWithArrayOfPoints(lastFivePoints)
}

Answer 1

你需要转换ArraySlice至 Array使用方法Array(Slice<Type>)

if (self.points?.count >= 5) {
    let lastFivePoints = Array(self.points![(self.points!.count-5)..<self.points!.count])
    let angle = VectorCalculator.angleWithArrayOfPoints(lastFivePoints)
}