swift 判断当前设备网络是否可用

判断当前网络是否可用的方法，需要导入SystemConfiguration.framework

import Foundationimport SystemConfigurationpublic class Reachability {    class func isConnectedToNetwork() -> Bool {        var zeroAddress = sockaddr_in(sin_len: 0, sin_family: 0, sin_port: 0, sin_addr: in_addr(s_addr: 0), sin_zero: (0, 0, 0, 0, 0, 0, 0, 0))        zeroAddress.sin_len = UInt8(sizeofValue(zeroAddress))        zeroAddress.sin_family = sa_family_t(AF_INET)        let defaultRouteReachability = withUnsafePointer(&zeroAddress) {            SCNetworkReachabilityCreateWithAddress(nil, UnsafePointer($0)).takeRetainedValue()        }        var flags: SCNetworkReachabilityFlags = 0        if SCNetworkReachabilityGetFlags(defaultRouteReachability, &flags) == 0 {            return false        }        let isReachable = (flags & UInt32(kSCNetworkFlagsReachable)) != 0        let needsConnection = (flags & UInt32(kSCNetworkFlagsConnectionRequired)) != 0        return (isReachable && !needsConnection) ? true : false    }}

调用

if Reachability.isConnectedToNetwork(){      println("网络正常") }else{          println("网络异常")    }