如何在swift中使用NSRange？

struct NSRange : Equatable, Hashable, Comparable {
    var location: Int
    var length: Int
}

let range = NSRange(location: 5, length: 3)

let str = "Hello, World!"
if let subStr = str.substring(with: range) {
    print(subStr)  // 输出 "World"
}

let array = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
let subArray = Array(array[range])
print(subArray)  // 输出 [6, 7, 8]

if let foundRange = str.range(of: "World", options: [], range: NSRange(location: 0, length: str.utf16.count), locale: nil) {
    print(foundRange.location)  // 输出 7
}

let swiftRange = 5..<8
let nsRange = NSRange(swiftRange, in: str)

// 反向转换
if let swiftRangeAgain = Range(nsRange, in: str) {
    print(Array(str[swiftRangeAgain]))  // 输出 ["W", "o", "r"]
}

if range.location + range.length <= str.count {
    // 安全地使用 range
} else {
    // 处理错误情况
}