废话不说，直接上代码：

 private func fetchNetInfo() -> [String : AnyObject]{
        
        let interfaceNames = CNCopySupportedInterfaces()
        var SSIDInfo = [String : AnyObject]()
        guard interfaceNames != nil else {
            return SSIDInfo
        }
        for interface in interfaceNames as! [CFString] {
            print("Looking up SSID info for \(interface)") // en0
            if let info = CNCopyCurrentNetworkInfo(interface as CFString){
                SSIDInfo = info as! [String : AnyObject]
            }
            for d in SSIDInfo.keys {
                print("\(d): \(SSIDInfo[d]!)")
            }
            if SSIDInfo.count > 0{
                break
            }
        }
        return SSIDInfo
        
    }

需要注意的是，iOS12以后 需要在xcode设置一下

注意：此时你的应用证书需要重新生成一下。