Swift 中的指针、指针算术和原始数据

在 Swift 编程语言中，指针、指针算术和原始数据是一些重要的概念。指针提供了直接访问和操作内存的能力，而指针算术则允许我们对指针进行加法、减法等运算。原始数据则是指未经处理的原始二进制数据。

swift
func swapInts(_ a: inout Int, _ b: inout Int) {
    let temp = a
    a = b
    b = temp
}
var x = 10
var y = 20
print("Before swapping: x = \(x), y = \(y)")
swapInts(&x, &y)
print("After swapping: x = \(x), y = \(y)")

swift
let numbers: [Int] = [10, 20, 30, 40, 50]
let pointer = UnsafePointer(numbers)
for i in 0..    let value = pointer.advanced(by: i).pointee
    print("Element at index \(i): \(value)")
}

swift
import Foundation
func readImageData(from fileURL: URL) -> Data? {
    let fileData = try? Data(contentsOf: fileURL)
    return fileData
}
let imageURL = URL(fileURLWithPath: "path/to/image.png")
if let imageData = readImageData(from: imageURL) {
    let pointer = UnsafeRawPointer((imageData as NSData).bytes)
    let imageSize = imageData.count
    print("Image size: \(imageSize) bytes")
}