如何确定当前用户位置是否在我的MKCoordinateRegion内？

import MapKit

func isUserInRegion(userLocation: CLLocationCoordinate2D, regionCenter: CLLocationCoordinate2D, radius: CLLocationDistance) -> Bool {
    let region = MKCoordinateRegionMakeWithDistance(regionCenter, radius, radius)
    return MKCoordinateRegionContainsCoordinate(region, userLocation)
}

// 示例用法
let userLocation = CLLocationCoordinate2D(latitude: 37.7749, longitude: -122.4194) // 当前用户位置坐标
let regionCenter = CLLocationCoordinate2D(latitude: 37.7749, longitude: -122.4194) // 区域中心坐标
let radius: CLLocationDistance = 1000 // 区域半径（单位：米）

let isInRegion = isUserInRegion(userLocation: userLocation, regionCenter: regionCenter, radius: radius)
print("用户是否在指定区域内：\(isInRegion)")