Swift-获取设备的WIFI IP地址

我需要在Swift中获取iOS设备的IP地址。这不是其他有关此问题的重复！如果没有wifi IP地址，我只需要获取WiFi IP地址-我需要处理它。关于堆栈溢出有一些疑问，但是只有返回IP地址的函数。例如（从如何快速获取IP地址）：

func getIFAddresses() -> [String] {
    var addresses = [String]()

    // Get list of all interfaces on the local machine:
    var ifaddr : UnsafeMutablePointer<ifaddrs> = nil
    if getifaddrs(&ifaddr) == 0 {

        // For each interface ...
        for (var ptr = ifaddr; ptr != nil; ptr = ptr.memory.ifa_next) {
            let flags = Int32(ptr.memory.ifa_flags)
            var addr = ptr.memory.ifa_addr.memory

            // Check for running IPv4, IPv6 interfaces. Skip the loopback interface.
            if (flags & (IFF_UP|IFF_RUNNING|IFF_LOOPBACK)) == (IFF_UP|IFF_RUNNING) {
                if addr.sa_family == UInt8(AF_INET) || addr.sa_family == UInt8(AF_INET6) {

                    // Convert interface address to a human readable string:
                    var hostname = [CChar](count: Int(NI_MAXHOST), repeatedValue: 0)
                    if (getnameinfo(&addr, socklen_t(addr.sa_len), &hostname, socklen_t(hostname.count),
                        nil, socklen_t(0), NI_NUMERICHOST) == 0) {
                            if let address = String.fromCString(hostname) {
                                addresses.append(address)
                            }
                    }
                }
            }
        }
        freeifaddrs(ifaddr)
    }

    return addresses
}

在这里，我得到2个值-来自移动互联网的地址（我认为）和需要的WiFi地址。还有其他方法可以获取仅WiFi IP地址吗？

根据几个SO线程（例如，iOS网络接口名称的确切含义是什么？pdp_ip是什么？ap是什么？），iOS设备上的WiFi接口始终具有名称“ en0”。

您的代码（这似乎是我在“如何迅速获取IP地址：”中回答的内容）检索所有正在运行的网络接口的IP地址的列表。可以轻松地修改它，使其仅返回“ en0”接口的IP地址，而实际上这正是我最初在该线程中回答的（这只是对如何以编程方式获取iphone的IP地址的回答的快速翻译。）：

// Return IP address of WiFi interface (en0) as a String, or `nil`
func getWiFiAddress() -> String? {
    var address : String?

    // Get list of all interfaces on the local machine:
    var ifaddr : UnsafeMutablePointer<ifaddrs> = nil
    if getifaddrs(&ifaddr) == 0 {

        // For each interface ...
        var ptr = ifaddr
        while ptr != nil {
            defer { ptr = ptr.memory.ifa_next }

            let interface = ptr.memory

            // Check for IPv4 or IPv6 interface:
            let addrFamily = interface.ifa_addr.memory.sa_family
            if addrFamily == UInt8(AF_INET) || addrFamily == UInt8(AF_INET6) {

                // Check interface name:
                if let name = String.fromCString(interface.ifa_name) where name == "en0" {

                    // Convert interface address to a human readable string:
                    var hostname = [CChar](count: Int(NI_MAXHOST), repeatedValue: 0)
                    getnameinfo(interface.ifa_addr, socklen_t(interface.ifa_addr.memory.sa_len),
                                &hostname, socklen_t(hostname.count),
                                nil, socklen_t(0), NI_NUMERICHOST)
                    address = String.fromCString(hostname)
                }
            }
        }
        freeifaddrs(ifaddr)
    }

    return address
}

用法：

if let addr = getWiFiAddress() {
    print(addr)
} else {
    print("No WiFi address")
}

Swift 3的更新：除了对Swift 3的许多更改采用代码之外 ，对所有接口进行迭代现在还可以使用新的通用 sequence()函数：

千万不要忘记添加#include <ifaddrs.h>在你的桥接报

// Return IP address of WiFi interface (en0) as a String, or `nil`
func getWiFiAddress() -> String? {
    var address : String?

    // Get list of all interfaces on the local machine:
    var ifaddr : UnsafeMutablePointer<ifaddrs>?
    guard getifaddrs(&ifaddr) == 0 else { return nil }
    guard let firstAddr = ifaddr else { return nil }

    // For each interface ...
    for ifptr in sequence(first: firstAddr, next: { $0.pointee.ifa_next }) {
        let interface = ifptr.pointee

        // Check for IPv4 or IPv6 interface:
        let addrFamily = interface.ifa_addr.pointee.sa_family
        if addrFamily == UInt8(AF_INET) || addrFamily == UInt8(AF_INET6) {

            // Check interface name:
            let name = String(cString: interface.ifa_name)
            if  name == "en0" {

                // Convert interface address to a human readable string:
                var hostname = [CChar](repeating: 0, count: Int(NI_MAXHOST))
                getnameinfo(interface.ifa_addr, socklen_t(interface.ifa_addr.pointee.sa_len),
                            &hostname, socklen_t(hostname.count),
                            nil, socklen_t(0), NI_NUMERICHOST)
                address = String(cString: hostname)
            }
        }
    }
    freeifaddrs(ifaddr)

    return address
}

对于那些寻求除WIFI IP之外的内容的人，您可以稍微修改一下此代码

func getAddress(for network: Network) -> String? {
    var address: String?

    // Get list of all interfaces on the local machine:
    var ifaddr: UnsafeMutablePointer<ifaddrs>?
    guard getifaddrs(&ifaddr) == 0 else { return nil }
    guard let firstAddr = ifaddr else { return nil }

    // For each interface ...
    for ifptr in sequence(first: firstAddr, next: { $0.pointee.ifa_next }) {
        let interface = ifptr.pointee

        // Check for IPv4 or IPv6 interface:
        let addrFamily = interface.ifa_addr.pointee.sa_family
        if addrFamily == UInt8(AF_INET) || addrFamily == UInt8(AF_INET6) {

            // Check interface name:
            let name = String(cString: interface.ifa_name)
            if name == network.rawValue {

                // Convert interface address to a human readable string:
                var hostname = [CChar](repeating: 0, count: Int(NI_MAXHOST))
                getnameinfo(interface.ifa_addr, socklen_t(interface.ifa_addr.pointee.sa_len),
                            &hostname, socklen_t(hostname.count),
                            nil, socklen_t(0), NI_NUMERICHOST)
                address = String(cString: hostname)
            }
        }
    }
    freeifaddrs(ifaddr)

    return address
}

enum Network: String {
    case wifi = "en0"
    case cellular = "pdp_ip0"
    //... case ipv4 = "ipv4"
    //... case ipv6 = "ipv6"
}

然后，我们也可以访问蜂窝IP。

guard let wifiIp = getAddress(for: .wifi) else { return }

和

guard let cellularIp = getAddress(for: .cellular) else { return }

创建桥接头并包含#include <ifaddrs.h>在其中。

然后写这个方法

func getIFAddresses() -> [String] {
var addresses = [String]()

// Get list of all interfaces on the local machine:
var ifaddr : UnsafeMutablePointer<ifaddrs> = nil
if getifaddrs(&ifaddr) == 0 {

    // For each interface ...
    for (var ptr = ifaddr; ptr != nil; ptr = ptr.memory.ifa_next) {
        let flags = Int32(ptr.memory.ifa_flags)
        var addr = ptr.memory.ifa_addr.memory

        // Check for running IPv4, IPv6 interfaces. Skip the loopback interface.
        if (flags & (IFF_UP|IFF_RUNNING|IFF_LOOPBACK)) == (IFF_UP|IFF_RUNNING) {
            if addr.sa_family == UInt8(AF_INET) || addr.sa_family == UInt8(AF_INET6) {

                // Convert interface address to a human readable string:
                var hostname = [CChar](count: Int(NI_MAXHOST), repeatedValue: 0)
                if (getnameinfo(&addr, socklen_t(addr.sa_len), &hostname, socklen_t(hostname.count),
                    nil, socklen_t(0), NI_NUMERICHOST) == 0) {
                        if let address = String.fromCString(hostname) {
                            addresses.append(address)
                        }
                }
            }
        }
    }
    freeifaddrs(ifaddr)
}

  return addresses
}

当我在viewController中调用此方法时，就像 var arr : NSArray = self.getIFAddresses()在控制台中得到完美响应一样

IP ：（“ 10.0.0.94”）

从这个数组中，您可以随时随地访问它。希望能帮助到你

获取wifi，有线和蜂窝网络的IPAddress（swift 5）

func getIPAddress() -> String {
    var address: String?
    var ifaddr: UnsafeMutablePointer<ifaddrs>? = nil
    if getifaddrs(&ifaddr) == 0 {
        var ptr = ifaddr
        while ptr != nil {
            defer { ptr = ptr?.pointee.ifa_next }

            guard let interface = ptr?.pointee else { return "" }
            let addrFamily = interface.ifa_addr.pointee.sa_family
            if addrFamily == UInt8(AF_INET) || addrFamily == UInt8(AF_INET6) {

                // wifi = ["en0"]
                // wired = ["en2", "en3", "en4"]
                // cellular = ["pdp_ip0","pdp_ip1","pdp_ip2","pdp_ip3"]

                let name: String = String(cString: (interface.ifa_name))
                if  name == "en0" || name == "en2" || name == "en3" || name == "en4" || name == "pdp_ip0" || name == "pdp_ip1" || name == "pdp_ip2" || name == "pdp_ip3" {
                    var hostname = [CChar](repeating: 0, count: Int(NI_MAXHOST))
                    getnameinfo(interface.ifa_addr, socklen_t((interface.ifa_addr.pointee.sa_len)), &hostname, socklen_t(hostname.count), nil, socklen_t(0), NI_NUMERICHOST)
                    address = String(cString: hostname)
                }
            }
        }
        freeifaddrs(ifaddr)
    }
    return address ?? ""
}

如何使用

let strIPAddress : String = self.getIPAddress()
print("IPAddress :: \(strIPAddress)")

注意：在您的项目的Bridging-Header文件中添加以下内容

#include<ifaddrs.h>

Swift 4-获取设备的IP地址：

加 #include<ifaddrs.h>您的桥接头。

这是获取IP地址所需的框架。

class func getIPAddress() -> String? {
        var address: String?
        var ifaddr: UnsafeMutablePointer<ifaddrs>? = nil
        if getifaddrs(&ifaddr) == 0 {
            var ptr = ifaddr
            while ptr != nil {
                defer { ptr = ptr?.pointee.ifa_next }

                let interface = ptr?.pointee
                let addrFamily = interface?.ifa_addr.pointee.sa_family
                if addrFamily == UInt8(AF_INET) || addrFamily == UInt8(AF_INET6) {

                    if let name: String = String(cString: (interface?.ifa_name)!), name == "en0" {
                        var hostname = [CChar](repeating: 0, count: Int(NI_MAXHOST))
                        getnameinfo(interface?.ifa_addr, socklen_t((interface?.ifa_addr.pointee.sa_len)!), &hostname, socklen_t(hostname.count), nil, socklen_t(0), NI_NUMERICHOST)
                        address = String(cString: hostname)
                    }
                }
            }
            freeifaddrs(ifaddr)
        }
        return address
}

Swift 4.2UIDevice扩展可避免强制拆包并支持蜂窝和有线IP地址：

import UIKit

extension UIDevice {

    private struct InterfaceNames {
        static let wifi = ["en0"]
        static let wired = ["en2", "en3", "en4"]
        static let cellular = ["pdp_ip0","pdp_ip1","pdp_ip2","pdp_ip3"]
        static let supported = wifi + wired + cellular
    }

    func ipAddress() -> String? {
        var ipAddress: String?
        var ifaddr: UnsafeMutablePointer<ifaddrs>?

        if getifaddrs(&ifaddr) == 0 {
            var pointer = ifaddr

            while pointer != nil {
                defer { pointer = pointer?.pointee.ifa_next }

                guard
                    let interface = pointer?.pointee,
                    interface.ifa_addr.pointee.sa_family == UInt8(AF_INET) || interface.ifa_addr.pointee.sa_family == UInt8(AF_INET6),
                    let interfaceName = interface.ifa_name,
                    let interfaceNameFormatted = String(cString: interfaceName, encoding: .utf8),
                    InterfaceNames.supported.contains(interfaceNameFormatted)
                    else { continue }

                var hostname = [CChar](repeating: 0, count: Int(NI_MAXHOST))

                getnameinfo(interface.ifa_addr,
                            socklen_t(interface.ifa_addr.pointee.sa_len),
                            &hostname,
                            socklen_t(hostname.count),
                            nil,
                            socklen_t(0),
                            NI_NUMERICHOST)

                guard
                    let formattedIpAddress = String(cString: hostname, encoding: .utf8),
                    !formattedIpAddress.isEmpty
                    else { continue }

                ipAddress = formattedIpAddress
                break
            }

            freeifaddrs(ifaddr)
        }

        return ipAddress
    }

}

用法：

UIDevice.current.ipAddress()

您可以使用以下代码获取IP地址：

注意：我使用可达性，以便在WiFi更改为另一个IP地址时捕获新的IP地址。

1. 在Podfile文件中

   pod 'ReachabilitySwift' 接着 install pod

2. 在AppDelegate.swift文件中import ReachabilitySwift

   注意：如果它提示无法找到ReachabilitySwift模块的错误，则只需将其复制并粘贴。有用！

3. didFinishLaunchingOptions 功能

   NotificationCenter.default.addObserver(self, selector: #selector(self.reachabilityChanged), name: ReachabilityChangedNotification, object: reachability)
   
   do{
       try reachability.startNotifier()
   }
   catch {
       print("could not start reachability notifier")
   } 
   

4. 然后将以下代码复制粘贴到AppDelegate文件中

   func reachabilityChanged(note: NSNotification) {
   
       let reachability = note.object as! Reachability
   
       if reachability.isReachable {
           if reachability.isReachableViaWiFi {
               print("Reachable via WiFi")
           } else {
               print("Reachable via Cellular")
           }
   
           setIPAddress()
       } else {
           ipAddress = "" // No IP captures
           print("Network not reachable")
       }
   }
   
   func setIPAddress() {
       if let addr = self.getWiFiAddress() {
           print("ipAddress : \(addr)")
           ipAddress = addr
       } else {
           ipAddress = "" // No IP captures
           print("No WiFi address")
       }
   }
   
   // Return IP address of WiFi interface (en0) as a String, or `nil`
   func getWiFiAddress() -> String? {
       var address : String?
   
       // Get list of all interfaces on the local machine:
       var ifaddr : UnsafeMutablePointer<ifaddrs>?
       guard getifaddrs(&ifaddr) == 0 else { return nil }
       guard let firstAddr = ifaddr else { return nil }
   
       // For each interface ...
       for ifptr in sequence(first: firstAddr, next: { $0.pointee.ifa_next }) {
           let interface = ifptr.pointee
   
           // Check for IPv4 or IPv6 interface:
           let addrFamily = interface.ifa_addr.pointee.sa_family
           if addrFamily == UInt8(AF_INET) || addrFamily == UInt8(AF_INET6) {
   
               // Check interface name:
               let name = String(cString: interface.ifa_name)
               if  name == "en0" {
   
                   // Convert interface address to a human readable string:
                   var addr = interface.ifa_addr.pointee
                   var hostname = [CChar](repeating: 0, count: Int(NI_MAXHOST))
                   getnameinfo(&addr, socklen_t(interface.ifa_addr.pointee.sa_len),
                               &hostname, socklen_t(hostname.count),
                               nil, socklen_t(0), NI_NUMERICHOST)
                   address = String(cString: hostname)
               }
           }
       }
       freeifaddrs(ifaddr)
   
       return address
   }
   

5. 将此添加到Bridging-Header文件中 #include<ifaddrs.h>

   如果您没有此文件，则可以创建它。检查此链接

6。

func applicationWillEnterForeground(_ application: UIApplication) {
        // Post notification
        NotificationCenter.default.post(name: ReachabilityChangedNotification, object: reachability)
        // Called as part of the transition from the background to the active state; here you can undo many of the changes made on entering the background.
    }

7. 如果要删除观察者，则：

   reachability.stopNotifier()  
   
   NSNotificationCenter.defaultCenter().removeObserver(self,name: ReachabilityChangedNotification,object: reachability)
   

func getIPAddress() -> String {
    var address: String = "error"

    var interfaces: ifaddrs? = nil

    var temp_addr: ifaddrs? = nil
    var success: Int = 0
    // retrieve the current interfaces - returns 0 on success
    success = getifaddrs(interfaces)
    if success == 0 {
        // Loop through linked list of interfaces
        temp_addr = interfaces
        while temp_addr != nil {
            if temp_addr?.ifa_addr?.sa_family == AF_INET {
                // Check if interface is en0 which is the wifi connection on the iPhone
                if (String(utf8String: temp_addr?.ifa_name) == "en0") {
                    // Get NSString from C String
                    address = String(utf8String: inet_ntoa((temp_addr?.ifa_addr as? sockaddr_in)?.sin_addr))
                }
            }
            temp_addr = temp_addr?.ifa_next
        }
    }
        // Free memory
    freeifaddrs(interfaces)
    return address
}

这里的所有答案都只给出了wifi的IP地址，而不是有线或蜂窝网络。以下代码段可用于wifi /有线/蜂窝情况：

func getIPAddressForCellOrWireless()-> String? {

    let WIFI_IF : [String] = ["en0"]
    let KNOWN_WIRED_IFS : [String] = ["en2", "en3", "en4"]
    let KNOWN_CELL_IFS : [String] = ["pdp_ip0","pdp_ip1","pdp_ip2","pdp_ip3"]

    var addresses : [String : String] = ["wireless":"",
                                         "wired":"",
                                         "cell":""]

    var address: String?
    var ifaddr: UnsafeMutablePointer<ifaddrs>? = nil
    if getifaddrs(&ifaddr) == 0 {

        var ptr = ifaddr
        while ptr != nil {
            defer { ptr = ptr?.pointee.ifa_next } // memory has been renamed to pointee in swift 3 so changed memory to pointee

            let interface = ptr?.pointee
            let addrFamily = interface?.ifa_addr.pointee.sa_family
            if addrFamily == UInt8(AF_INET) || addrFamily == UInt8(AF_INET6) {

                if let name: String = String(cString: (interface?.ifa_name)!), (WIFI_IF.contains(name) || KNOWN_WIRED_IFS.contains(name) || KNOWN_CELL_IFS.contains(name)) {

                    // String.fromCString() is deprecated in Swift 3. So use the following code inorder to get the exact IP Address.
                    var hostname = [CChar](repeating: 0, count: Int(NI_MAXHOST))
                    getnameinfo(interface?.ifa_addr, socklen_t((interface?.ifa_addr.pointee.sa_len)!), &hostname, socklen_t(hostname.count), nil, socklen_t(0), NI_NUMERICHOST)
                    address = String(cString: hostname)
                    if WIFI_IF.contains(name){
                        addresses["wireless"] =  address
                    }else if KNOWN_WIRED_IFS.contains(name){
                        addresses["wired"] =  address
                    }else if KNOWN_CELL_IFS.contains(name){
                        addresses["cell"] =  address
                    }
                }

            }
        }
    }
    freeifaddrs(ifaddr)

    var ipAddressString : String?
    let wirelessString = addresses["wireless"]
    let wiredString = addresses["wired"]
    let cellString = addresses["cell"]
    if let wirelessString = wirelessString, wirelessString.count > 0{
        ipAddressString = wirelessString
    }else if let wiredString = wiredString, wiredString.count > 0{
        ipAddressString = wiredString
    }else if let cellString = cellString, cellString.count > 0{
        ipAddressString = cellString
    }
    return ipAddressString
}

Swift 5清理

我更新了上面的答案，以消除任何强制展开和一些SwiftLint清理的情况。

 class func getIPAddress() -> String? {
        var address: String?
        var ifaddr: UnsafeMutablePointer<ifaddrs>?
        if getifaddrs(&ifaddr) == 0 {
            var ptr = ifaddr
            while ptr != nil {
                defer { ptr = ptr?.pointee.ifa_next }
                let interface = ptr?.pointee
                let addrFamily = interface?.ifa_addr.pointee.sa_family
                if addrFamily == UInt8(AF_INET) || addrFamily == UInt8(AF_INET6),
                    let cString = interface?.ifa_name,
                    String(cString: cString) == "en0",
                    let saLen = (interface?.ifa_addr.pointee.sa_len) {
                    var hostname = [CChar](repeating: 0, count: Int(NI_MAXHOST))
                    let ifaAddr = interface?.ifa_addr
                    getnameinfo(ifaAddr,
                                socklen_t(saLen),
                                &hostname,
                                socklen_t(hostname.count),
                                nil,
                                socklen_t(0),
                                NI_NUMERICHOST)
                    address = String(cString: hostname)
                }
            }
            freeifaddrs(ifaddr)
        }
        return address
    }

如果只需要IPv4响应作为输出，则只需修改Martin R的解决方案即可。

 func getWiFiAddress() -> String? {
    var address : String?

    // Get list of all interfaces on the local machine:
    var ifaddr : UnsafeMutablePointer<ifaddrs>?
    guard getifaddrs(&ifaddr) == 0 else { return nil }
    guard let firstAddr = ifaddr else { return nil }

    // For each interface ...
    for ifptr in sequence(first: firstAddr, next: { $0.pointee.ifa_next }) {
        let interface = ifptr.pointee

        // Check for IPv4 or IPv6 interface:
        let addrFamily = interface.ifa_addr.pointee.sa_family
        //if addrFamily == UInt8(AF_INET) || addrFamily == UInt8(AF_INET6) {  // **ipv6 committed
        if addrFamily == UInt8(AF_INET){

            // Check interface name:
            let name = String(cString: interface.ifa_name)
            if  name == "en0" {

                // Convert interface address to a human readable string:
                var hostname = [CChar](repeating: 0, count: Int(NI_MAXHOST))
                getnameinfo(interface.ifa_addr, socklen_t(interface.ifa_addr.pointee.sa_len),
                            &hostname, socklen_t(hostname.count),
                            nil, socklen_t(0), NI_NUMERICHOST)
                address = String(cString: hostname)
            }
        }
    }
    freeifaddrs(ifaddr)

    return address
}

用法：

if let addr = getWiFiAddress() {
   print(addr)
} else {
   print("No WiFi address")
}

另一个解决方案有点不同，那就是使用Ipify，这是一项免费的轻量级服务，您可以ping以获取IP

这里是他们的Swift示例：

let url = URL(string: "https://api.ipify.org")

do {
    if let url = url {
        let ipAddress = try String(contentsOf: url)
        print("My public IP address is: " + ipAddress)
    }
} catch let error {
    print(error)
}

支持IPV4和IPV6

使它成为UIDevice的扩展并使用UIDevice.current.getIPAdress（）进行调用

private struct Interfaces {
    // INTERFACCIE SUPPORT
    static let wifi = ["en0"]
    static let cellular = ["pdp_ip0","pdp_ip1","pdp_ip2","pdp_ip3"]
    static let supported = wifi + cellular
}


func getIPAdress() -> (String?,String?)? {
    var ip4Adress: String?
    var ip6Adress: String?
    var hasAdress: UnsafeMutablePointer<ifaddrs>?


    if getifaddrs(&hasAdress) == 0 {
        var pointer = hasAdress

        while pointer != nil {
            defer { pointer = pointer?.pointee.ifa_next}

            guard let interface = pointer?.pointee else {continue}

            // SEARCH FOR IPV4 OR IPV6 IN THE INTERFACE OF THE NODE
            // HERE I'M ALREADY LOOSING MY MIND
            // PRIORITY FOR IPV4 THAN IPV6
            if  interface.ifa_addr.pointee.sa_family == UInt8(AF_INET) {
                guard let ip4 = processInterface(interface: interface) else {
                    continue
                }
                ip4Adress = ip4
            }

            if interface.ifa_addr.pointee.sa_family == UInt8(AF_INET6) {
                guard let ip6 = processInterface(interface: interface) else {
                    continue
                }
                ip6Adress = ip6
            }
        }
        freeifaddrs(hasAdress)
    }
    return (ip4Adress, ip6Adress)
}



func processInterface(interface: ifaddrs) -> String? {

    var ipAdress: String = ""
    guard
        let interfaceName = interface.ifa_name else {return nil}
                       guard
                           let interfaceNameFormatted = String(cString: interfaceName, encoding: .utf8) else {return nil}
    guard Interfaces.supported.contains(interfaceNameFormatted) else {return nil}

                       var hostname = [CChar](repeating: 0, count: Int(NI_MAXHOST))

                       print(interfaceNameFormatted)

                       // CONVERT THE SOCKET ADRESS TO A CORRESPONDING HOST AND SERVICE
                       getnameinfo(interface.ifa_addr,
                                   socklen_t(interface.ifa_addr.pointee.sa_len),
                                   &hostname, socklen_t(hostname.count),
                                   nil,
                                   socklen_t(0),
                                   NI_NUMERICHOST)

                       guard let formattedIpAdress = String(cString: hostname, encoding: .utf8) else {return nil}
                       if !formattedIpAdress.isEmpty {
                           ipAdress = formattedIpAdress
                       }
    return ipAdress
}

此类使用NWPathMonitor监视设备接口。您可以设置一个更新处理程序，以通知您有关接口状态的更改。选择是否要跟踪ipv4或ipv6并检查status.interfaceType == .wifi以查看活动接口是否为wifi

用法：

let monitor = IPMonitor(ipType: .ipv4) 
monitor.pathUpdateHandler = { status in 
  print("\(status.debugDescription)")
}

类：

import Foundation
import Network

class IPMonitor {
    
    enum InterfaceType: String {
        case cellular = "cellular"
        case wifi = "wifi"
        case wired = "wired"
        case loopback = "loopback"
        case other = "other"
        case notFound = "not found"
    }
    
    enum IPType: String {
        case ipv4 = "IPv4"
        case ipv6 = "ipV6"
        case unknown = "unknown"
    }
    
    struct Status {
        var name = "unknown"
        var interfaceType: InterfaceType = InterfaceType.notFound
        var ip: [String] = []
        var ipType: IPType = IPType.unknown
        
        var debugDescription: String {
            let result = "Interface: \(name)/\(interfaceType.rawValue), \(ipType.rawValue)\(ip.debugDescription)"
            return result
        }
    }
    
    private let monitor = NWPathMonitor()
    private let queue = DispatchQueue(label: "ip_monitor_queue")
    
    final var pathUpdateHandler: ((Status) -> Void)?
    
    init(ipType: IPType) {
        monitor.pathUpdateHandler = { path in
            let name = self.getInterfaceName(path: path)
            let type = self.getInterfaceType(path: path)
            let ip = self.getIPAddresses(interfaceName: name, ipType: ipType)
            let status = Status(name: name, interfaceType: type, ip: ip, ipType: ipType)
            //print("\(status)")
            self.pathUpdateHandler?(status)
        }
        monitor.start(queue: queue)
    }
    
    private func getInterfaceName(path: NWPath) -> String {
        if let name = path.availableInterfaces.first?.name {
            return name
        }
        return "unknown"
    }
    
    private func getInterfaceType(path: NWPath) -> InterfaceType {
        if let type = path.availableInterfaces.first?.type {
            switch type {
            case NWInterface.InterfaceType.cellular:
                return InterfaceType.cellular
            case NWInterface.InterfaceType.wifi:
                return InterfaceType.wifi
            case NWInterface.InterfaceType.wiredEthernet:
                return InterfaceType.wired
            case NWInterface.InterfaceType.loopback:
                return InterfaceType.loopback
            default:
                return InterfaceType.other
            }
        }
        
        return InterfaceType.notFound
    }
    
    private func getIPAddresses(interfaceName: String, ipType: IPType)-> [String]{
        var addresses: [String] = []
        var ifaddr: UnsafeMutablePointer<ifaddrs>? = nil
        if getifaddrs(&ifaddr) == 0 {
            var ptr = ifaddr
            while ptr != nil {
                defer { ptr = ptr?.pointee.ifa_next }
                let interface = ptr?.pointee
                let addrFamily = interface?.ifa_addr.pointee.sa_family
                if (addrFamily == UInt8(AF_INET) && ipType == .ipv4)
                    || (addrFamily == UInt8(AF_INET6) && ipType == .ipv6) {
                    let name = String(cString: (interface?.ifa_name)!)
                    if name == interfaceName {
                        var hostname = [CChar](repeating: 0, count: Int(NI_MAXHOST))
                        getnameinfo(interface?.ifa_addr, socklen_t((interface?.ifa_addr.pointee.sa_len)!), &hostname, socklen_t(hostname.count), nil, socklen_t(0), NI_NUMERICHOST)
                        addresses.append(String(cString: hostname))
                    }
                }
            }
        }
        freeifaddrs(ifaddr)
        
        return addresses
    }
}

对于Mac上的Swift-Swift 4：这样，您还可以从Wifi中找到IP（不仅是以太网）

func getWiFiAddress() -> String? {
    var address : String?

    // Get list of all interfaces on the local machine:
    var ifaddr : UnsafeMutablePointer<ifaddrs>?
    guard getifaddrs(&ifaddr) == 0 else { return nil }
    guard let firstAddr = ifaddr else { return nil }

    // For each interface ...
    for ifptr in sequence(first: firstAddr, next: { $0.pointee.ifa_next }) {
        let interface = ifptr.pointee

        // Check for IPv4 or IPv6 interface:
        let addrFamily = interface.ifa_addr.pointee.sa_family
        if addrFamily == UInt8(AF_INET) || addrFamily == UInt8(AF_INET6) {

            // Check interface name:
            let name = String(cString: interface.ifa_name)
            if  name == "en0" {

                // Convert interface address to a human readable string:
                var hostname = [CChar](repeating: 0, count: Int(NI_MAXHOST))
                getnameinfo(interface.ifa_addr, socklen_t(interface.ifa_addr.pointee.sa_len),
                            &hostname, socklen_t(hostname.count),
                            nil, socklen_t(0), NI_NUMERICHOST)
                address = String(cString: hostname)
            } else if name == "en1" {
                // Convert interface address to a human readable string:
                var hostname = [CChar](repeating: 0, count: Int(NI_MAXHOST))
                getnameinfo(interface.ifa_addr, socklen_t(interface.ifa_addr.pointee.sa_len),
                            &hostname, socklen_t(hostname.count),
                            nil, socklen_t(1), NI_NUMERICHOST)
                address = String(cString: hostname)
            }
        }
    }
    freeifaddrs(ifaddr)

    return address
}

NWInterface.InterfaceType基于上述某些答案的扩展：

import Network

extension NWInterface.InterfaceType {
    var names : [String]? {
        switch self {
        case .wifi: return ["en0"]
        case .wiredEthernet: return ["en2", "en3", "en4"]
        case .cellular: return ["pdp_ip0","pdp_ip1","pdp_ip2","pdp_ip3"]
        default: return nil
        }
    }

    func address(family: Int32) -> String?
    {
        guard let names = names else { return nil }
        var address : String?
        for name in names {
            guard let nameAddress = self.address(family: family, name: name) else { continue }
            address = nameAddress
            break
        }
        return address
    }

    func address(family: Int32, name: String) -> String? {
        var address: String?

        // Get list of all interfaces on the local machine:
        var ifaddr: UnsafeMutablePointer<ifaddrs>?
        guard getifaddrs(&ifaddr) == 0, let firstAddr = ifaddr else { return nil }

        // For each interface ...
        for ifptr in sequence(first: firstAddr, next: { $0.pointee.ifa_next }) {
            let interface = ifptr.pointee

            let addrFamily = interface.ifa_addr.pointee.sa_family
            if addrFamily == UInt8(family)
            {
                // Check interface name:
                if name == String(cString: interface.ifa_name) {
                    // Convert interface address to a human readable string:
                    var hostname = [CChar](repeating: 0, count: Int(NI_MAXHOST))
                    getnameinfo(interface.ifa_addr, socklen_t(interface.ifa_addr.pointee.sa_len),
                                &hostname, socklen_t(hostname.count),
                                nil, socklen_t(0), NI_NUMERICHOST)
                    address = String(cString: hostname)
                }
            }
        }
        freeifaddrs(ifaddr)

        return address
    }

    var ipv4 : String? { self.address(family: AF_INET) }
    var ipv6 : String? { self.address(family: AF_INET6) }
}

用法：

对于蜂窝电话的ipv4： NWInterface.InterfaceType.cellular.ipv4

enum Network: String {
    case wifi = "en0"
    case cellular = "pdp_ip0"
//    case en1 = "en1"
//    case lo = "lo0"
}

// get ipv4 or ipv6 address
extension UIDevice {
    
    func address(family: Int32, for network: Network) -> String? {
        var address: String?

        // Get list of all interfaces on the local machine:
        var ifaddr: UnsafeMutablePointer<ifaddrs>?
        guard getifaddrs(&ifaddr) == 0, let firstAddr = ifaddr else { return nil }

        // For each interface ...
        for ifptr in sequence(first: firstAddr, next: { $0.pointee.ifa_next }) {
            let interface = ifptr.pointee

            let addrFamily = interface.ifa_addr.pointee.sa_family
            if addrFamily == UInt8(family) {
                // Check interface name:
                let name = String(cString: interface.ifa_name)
                if name == network.rawValue {
                    // Convert interface address to a human readable string:
                    var hostname = [CChar](repeating: 0, count: Int(NI_MAXHOST))
                    getnameinfo(interface.ifa_addr, socklen_t(interface.ifa_addr.pointee.sa_len),
                                &hostname, socklen_t(hostname.count),
                                nil, socklen_t(0), NI_NUMERICHOST)
                    address = String(cString: hostname)
                }
            }
        }
        freeifaddrs(ifaddr)

        return address
    }
    
    func ipv4(for network: Network) -> String? {
        self.address(family: AF_INET, for: network)
    }
    
    func ipv6(for network: Network) -> String? {
        self.address(family: AF_INET6, for: network)
    }
    
    // get all addresses
    func getIFAddresses() -> [String] {
        var addresses = [String]()
        
        // Get list of all interfaces on the local machine:
        var ifaddr : UnsafeMutablePointer<ifaddrs>?
        guard getifaddrs(&ifaddr) == 0 else { return [] }
        guard let firstAddr = ifaddr else { return [] }
        
        // For each interface ...
        for ptr in sequence(first: firstAddr, next: { $0.pointee.ifa_next }) {
            let flags = Int32(ptr.pointee.ifa_flags)
            let addr = ptr.pointee.ifa_addr.pointee
            
            // Check for running IPv4, IPv6 interfaces. Skip the loopback interface.
            if (flags & (IFF_UP|IFF_RUNNING|IFF_LOOPBACK)) == (IFF_UP|IFF_RUNNING) {
                if addr.sa_family == UInt8(AF_INET) || addr.sa_family == UInt8(AF_INET6) {
                    
                    // Convert interface address to a human readable string:
                    var hostname = [CChar](repeating: 0, count: Int(NI_MAXHOST))
                    if (getnameinfo(ptr.pointee.ifa_addr, socklen_t(addr.sa_len), &hostname, socklen_t(hostname.count),
                                    nil, socklen_t(0), NI_NUMERICHOST) == 0) {
                        let address = String(cString: hostname)
                        addresses.append(address)
                    }
                }
            }
        }
        
        freeifaddrs(ifaddr)
        
        return addresses
    }
}

如何使用

// for wifi
  let wifi = UIDevice.current.ipv4(for: .wifi) # ipv4
  let wifi6 = UIDevice.current.ipv6(for: .wifi) # ipv6

// for cellular
  let cellular = UIDevice.current.ipv4(for: .cellular) # ipv4
  let cellular6 = UIDevice.current.ipv6(for: .cellular) # ipv6

鉴于您已经有了套接字的文件描述符，这是Swift 5.2的解决方案。

// Depending on your case get the socket's file descriptor
// the way you want
let socketFd = foo()

// Get the remote address for that file descriptor
var addr: sockaddr_storage = sockaddr_storage()
var addr_len: socklen_t = socklen_t(MemoryLayout.size(ofValue: addr))

var hostBuffer = [CChar](repeating: 0, count: Int(NI_MAXHOST))

// Make local copy to avoid: "Overlapping accesses to 'addr', 
// but modification requires exclusive access; consider copying
// to a local variable"
let addrLen = addr.ss_len

withUnsafeMutablePointer(to: &addr) {
    $0.withMemoryRebound(to: sockaddr.self, capacity: 1) {
        if getpeername(socketFd, $0, &addr_len) != 0 { return }
        
        getnameinfo($0, socklen_t(addrLen), &hostBuffer, socklen_t(hostBuffer.count), nil, 0, NI_NUMERICHOST)
    }
}

let connectedHost = String(cString: hostBuffer, encoding: .utf8)