Windows phone 8 学习笔记(3) 通信

ycycoco

　　Windows phone 8 可利用的数据通信方式比较广泛，在硬件支持的前提下，我们可以利用WiFi、蓝牙、临近感应等多种方式。数据交互一般通过套接字来完成，我们将在本文详细的分析。
　　快速导航：
    一、WP8套接字
    二、蓝牙
    三、NFC
    四、获取网络状态
    五、访问web的几种方式

一、WP8套接字

1）创建套接字客户端
　　Windows phone 8中的套接字并不支持发布服务端，我们只能利用它在手机上创建套接字客户端，我们在此例中要用套接字去访问web服务器。首先，我们定义一个SocketClient来表示套接字客户端。


[C#]


    public class SocketClient
{
//缓存套接字对象以便在整个生命周期重用
Socket _socket = null;
// 信号通知对象，用于异步操作完成通知
static ManualResetEvent _clientDone = new ManualResetEvent(false);
///
/// 为每个异步调用设置超时时间
///
const int TIMEOUT_MILLISECONDS = 30000;
///
/// 数据缓冲区大小
///
const int MAX_BUFFER_SIZE = 2048 * 100;
///
/// 关闭套接字连接和释放所有相关的资源
///
public void Close()
{
if (_socket != null)
{
_socket.Close();
}
}
}

    这个客户端包含连接服务器、发送信息和接受信息三个方法。我们将如下代码加入SocketClient类：
    连接：
[C#]


        ///
/// 尝试用TCP套接字连接到指定主机端口
///
/// 主机名
/// 端口号
/// 描述连接结果
public string Connect(string hostName, int portNumber)
{
string result = string.Empty;
//创建一个终结点,主机名、端口号
DnsEndPoint hostEntry = new DnsEndPoint(hostName, portNumber);
//创建一个基于流，TCP套接字。
_socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
//套接字上下文
SocketAsyncEventArgs socketEventArg = new SocketAsyncEventArgs();
socketEventArg.RemoteEndPoint = hostEntry;
socketEventArg.Completed += new EventHandler(delegate(object s, SocketAsyncEventArgs e)
{
//执行的状态信息
result = e.SocketError.ToString();
//将当前线程设置为收到信息状态，这样被阻止的线程可以继续执行
_clientDone.Set();
});
//标识当前进程为未收到信息状态
_clientDone.Reset();
// 发送一个异步连接请求
_socket.ConnectAsync(socketEventArg);
//将当前线程阻止，直到当前线程收到信息或者超时时间已到
_clientDone.WaitOne(TIMEOUT_MILLISECONDS);
return result;
}

    发送消息：
[C#]


        ///
/// 向连接的服务器发送信息
///
/// 数据正文
/// 反馈
public string Send(string data)
{
string response = "操作超时";
//套接字是否准备好
if (_socket != null)
{
//套接字上下文
SocketAsyncEventArgs socketEventArg = new SocketAsyncEventArgs();
socketEventArg.RemoteEndPoint = _socket.RemoteEndPoint;
socketEventArg.UserToken = null;
socketEventArg.Completed += new EventHandler(delegate(object s, SocketAsyncEventArgs e)
{
response = e.SocketError.ToString();
_clientDone.Set();
});
byte[] payload = Encoding.UTF8.GetBytes(data);
socketEventArg.SetBuffer(payload, 0, payload.Length);
_clientDone.Reset();
_socket.SendAsync(socketEventArg);
_clientDone.WaitOne(TIMEOUT_MILLISECONDS);
}
else
{
response = "套接字没有准备好";
}
return response;
}

    接受消息：
[C#]


        ///
/// 从连接服务器接收数据
///
/// The data received from the server
public string Receive()
{
string response = "操作超时";
if (_socket != null)
{
SocketAsyncEventArgs socketEventArg = new SocketAsyncEventArgs();
socketEventArg.RemoteEndPoint = _socket.RemoteEndPoint;
//设置接收数据的缓冲区
socketEventArg.SetBuffer(new Byte[MAX_BUFFER_SIZE], 0, MAX_BUFFER_SIZE);
socketEventArg.Completed += new EventHandler(delegate(object s, SocketAsyncEventArgs e)
{
if (e.SocketError == SocketError.Success)
{
// Retrieve the data from the buffer
response = Encoding.UTF8.GetString(e.Buffer, e.Offset, e.BytesTransferred);
response = response.Trim('\0');
}
else
{
response = "错误：" + e.SocketError.ToString();
}
_clientDone.Set();
});
_clientDone.Reset();
_socket.ReceiveAsync(socketEventArg);
_clientDone.WaitOne(TIMEOUT_MILLISECONDS);
}
else
{
response = "套接字没有准备好";
}
return response;
}

2）通过套接字访问HTTP网站
　　现在我们有了套接字客户端，这个时候我们来做一个类似于浏览器的功能，我们模拟HTTP请求发送到web服务器，代码如下：


[XAML]


   




















[C#]


        private void Button_Click_1(object sender, RoutedEventArgs e)
{
string hostName = textbox1.Text.Replace("http://", string.Empty);
SocketClient client = new SocketClient();
//主机，端口号
textblok1.Text = client.Connect(hostName, 80);
//模拟一个HTTP Get请求
textblok1.Text = client.Send("GET http://" + hostName + " HTTP/1.0\r\nHost: " + hostName + "\r\n\r\n\r\n");
//等待相应
textblok1.Text = client.Receive();
}

　　

二、蓝牙
　　WP8蓝牙支持对等方应用连接，也支持其他蓝牙设备，下面我们看看如何连接到对等方应用和设备。

1）连接到对等方

[C#]


        //已经搜索到的对等方列表
IReadOnlyList peers;
// 开始连接到对等应用
async void AppToApp()
{
// 开始查找对等项，如果有这句话，即可使自己能够被其他蓝牙设备搜索到
PeerFinder.Start();
peers = await PeerFinder.FindAllPeersAsync();
if (peers.Count == 0)
{
// 没有发现
}
else
{
// 选择第一个对等应用
PeerInformation selectedPeer = peers[0];
// 连接到第一个对等方应用
var streamSocket = await PeerFinder.ConnectAsync(selectedPeer);
}
}

2）连接到设备
　　PeerFinder.AlternateIdentities["Bluetooth:Paired"] = ""; 查找所有已配对的设备。这样连接找到的设备对应的PeerInformation.ServiceName将为空，所以我们不能通过PeerFinder.ConnectAsync(selectedPeer);的方式去连接，具体示例如下：

[C#]


        //搜寻全部蓝牙设备并连接第一个
private async void AppToDevice()
{
// 搜索所有配对的设备
PeerFinder.AlternateIdentities["Bluetooth:Paired"] = "";
var pairedDevices = await PeerFinder.FindAllPeersAsync();
if (pairedDevices.Count == 0)
{
//没有发现设备
}
else
{
// 选择第一个连接的设备，此时selectedDevice.ServiceName为空
PeerInformation selectedDevice = pairedDevices[0];
// 主动创建一个StreamSocket
StreamSocket socket = new StreamSocket();
// 第二个参数是一个RFCOMM端口号，范围是1-30
await socket.ConnectAsync(selectedDevice.HostName, "1");
}
}

　　PeerFinder.AlternateIdentities["Bluetooth:SDP"] = "XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX";查找使用服务发现协议 (SDP) 并通过既定 GUID 播发服务的设备

[C#]


        //搜寻特定GUID的设备
private async void AppToDevice2()
{
PeerFinder.AlternateIdentities["Bluetooth:SDP"] = "XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX";
var pairedDevices = await PeerFinder.FindAllPeersAsync();
if (pairedDevices.Count == 0)
{
//没有发现设备
}
else
{
// 选择第一个连接的设备
PeerInformation selectedDevice = pairedDevices[0];
// 主动创建一个StreamSocket
StreamSocket socket = new StreamSocket();
// 这种情况下selectedDevice.ServiceName等于您指定的GUID
await socket.ConnectAsync(selectedDevice.HostName, selectedDevice.ServiceName);
}
}

3）侦听连接请求

[C#]


        public Page1()
{
InitializeComponent();
//侦听连接请求需要先添加事件
Loaded += MainPage_Loaded;
}
void MainPage_Loaded(object sender, RoutedEventArgs e)
{
//远程对等类异步连接时触发
PeerFinder.ConnectionRequested += PeerFinder_ConnectionRequested;
}
async void PeerFinder_ConnectionRequested(object sender, ConnectionRequestedEventArgs args)
{
// 获取到请求连接的对等方
var peer = args.PeerInformation;
// 回应连接
var streamSocket = await PeerFinder.ConnectAsync(peer);
}

4）发送消息

[C#]


        ///
/// 在已连接的情况下发送消息
///
///
public async void Send(StreamSocket socket, string msg)
{
var _dataWriter = new DataWriter(socket.OutputStream);
//写入消息的长度
uint strLength = _dataWriter.MeasureString(msg);
_dataWriter.WriteUInt32(strLength);
//写入消息的内容
_dataWriter.WriteString(msg);
uint numBytesWritten = await _dataWriter.StoreAsync();
}

5）接收消息

[C#]


        ///
/// 在已连接的情况下读取消息
///
///
public async Task Read(StreamSocket socket)
{
var _dataReader = new DataReader(socket.InputStream);
// 读取消息长度
await _dataReader.LoadAsync(sizeof(uint));
uint msgLength = (uint)_dataReader.ReadUInt32();
// 读取消息的内容
await _dataReader.LoadAsync(msgLength);
return _dataReader.ReadString(msgLength);
}

　　

三、NFC
　　当两个设备距离较近时，可以使用近场通信技术，本文演示一个使用近场通信制作聊天软件的例子。

[XAML]


        







[C#]


    public partial class MainPage : PhoneApplicationPage
{
ProximityDevice device;
long typeId = -1;
long msgId = -1;
public MainPage()
{
InitializeComponent();
device = ProximityDevice.GetDefault();
if (device == null)
{
IsEnabled = false;
textblock1.Text = "您的手机不支持NFC功能";
}
else
{
//设备进入NFC识别范围时触发
device.DeviceArrived += device_DeviceArrived;
//设备离开NFC识别范围时触发
device.DeviceDeparted += device_DeviceDeparted;
}
}
//设备进入NFC识别范围时触发
void device_DeviceArrived(ProximityDevice sender)
{
//创建消息订阅，创建好后就可以直接发消息了
typeId = sender.SubscribeForMessage("Windows.MyMsgType", MsgReceivedHandler);
Dispatcher.BeginInvoke(() => textblock1.Text = "连接状态：已连接");
}
//设备离开NFC识别范围时触发
void device_DeviceDeparted(ProximityDevice sender)
{
if (typeId != -1)
{
//取消消息订阅
sender.StopSubscribingForMessage(typeId);
typeId = -1;
}
Dispatcher.BeginInvoke(() => textblock1.Text = "连接状态：连接中断");
}
///
/// 接收到消息后的处理逻辑
///
void MsgReceivedHandler(ProximityDevice sender, ProximityMessage message)
{
Dispatcher.BeginInvoke(() =>
{
listbox1.Items.Add(("对方：" + message.DataAsString));
});
}
///
/// 发送消息按钮按下时
///
private void Button_Click_1(object sender, RoutedEventArgs e)
{
if (textbox1.Text != string.Empty)
{
listbox1.Items.Add("我：" + textbox1.Text);
if (msgId != -1)
device.StopPublishingMessage(msgId);
msgId = device.PublishMessage("Windows.MyMsgType", textbox1.Text);
}
}
}

　　现在我们看看在模拟器中的效果，如下图。模拟器中实现NFC的模拟效果请下载：http://proximitytapper.codeplex.com
　　


四、获取网络状态
　　很多时候，应用可能需要利用到网络，这个时候我们需要获取一些信息，比如网络是否连接，当前是连接到WiFi还是运营商蜂窝网络。这些信息关系到您的应用是否能正常工作，或者是否处于免费网络下可执行高流量下载等操作。

1. 数据感知
　　数据感知功能可以用来获取网络成本信息以及流量计划，帮助用户合理使用手机流量，我们看看使用方法。

[C#]


var connectionProfile = Windows.Networking.Connectivity.NetworkInformation.GetInternetConnectionProfile();
//网络接口类型
var ianaInterfaceType = connectionProfile.NetworkAdapter.IanaInterfaceType;
//连接成本信息
var connectionCost = connectionProfile.GetConnectionCost();
//当前的网络使用成本
var networkCostType = connectionCost.NetworkCostType;
//计划流量是否快用完
var approachingDataLimit = connectionCost.ApproachingDataLimit;
//是否超过计划流量
var overDataLimit = connectionCost.OverDataLimit;
//是否漫游
var roaming = connectionCost.Roaming;

2. 网络信息获取
　　我们可以通过API获取网络接口状态，检查手机数据网络以及WiFi连接情况等。

[XAML]


        













[C#]


        Socket socket;
protected override void OnNavigatedTo(System.Windows.Navigation.NavigationEventArgs e)
{
//移动运营商
textblock1.Text = DeviceNetworkInformation.CellularMobileOperator;

//网络信息
System.Text.StringBuilder sb = new System.Text.StringBuilder();
sb.Append("网络是否可用:  ");
sb.AppendLine(DeviceNetworkInformation.IsNetworkAvailable.ToString());
sb.Append("是否启用蜂窝数据:  ");
sb.AppendLine(DeviceNetworkInformation.IsCellularDataEnabled.ToString());
sb.Append("是否允许漫游:  ");
sb.AppendLine(DeviceNetworkInformation.IsCellularDataRoamingEnabled.ToString());
sb.Append("是否启用Wi-Fi:  ");
sb.AppendLine(DeviceNetworkInformation.IsWiFiEnabled.ToString());
//网络接口信息
sb.Append("网络接口类型:  ");
var networkInterfaceType = NetworkInterface.NetworkInterfaceType;
var networkInterfaceTypeString = networkInterfaceType.ToString() + "(" + InterfaceTypeConvert.Convert(networkInterfaceType) + ")";
sb.AppendLine(networkInterfaceTypeString);
sb.Append("网络接口子类型:  ");
var networkSubInterfaceTypeString = string.Empty;
DeviceNetworkInformation.ResolveHostNameAsync(new DnsEndPoint("www.baidu.com", 80),
new NameResolutionCallback(x =>
{
networkSubInterfaceTypeString = x.NetworkInterface.InterfaceSubtype.ToString() + "[" + InterfaceTypeConvert.ConvertSub(x.NetworkInterface.InterfaceSubtype) + "]";
sb.AppendLine(networkSubInterfaceTypeString);
Dispatcher.BeginInvoke(() => { textblock2.Text = sb.ToString(); });
}), null);

//套接字连接信息
DnsEndPoint hostEntry = new DnsEndPoint("www.baidu.com", 80);
socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
//设置连接要求，必须为使用蜂窝技术网络
socket.SetNetworkRequirement(NetworkSelectionCharacteristics.Cellular);
SocketAsyncEventArgs socketEventArg = new SocketAsyncEventArgs();
socketEventArg.RemoteEndPoint = hostEntry;
socketEventArg.Completed += new EventHandler(delegate(object s, SocketAsyncEventArgs e1)
{
NetworkInterfaceInfo netInterfaceInfo = socket.GetCurrentNetworkInterface();
StringBuilder sb2 = new StringBuilder();
sb2.AppendLine("最后更新: " + DateTime.Now.ToString());
sb2.Append("网络接口名: ");
sb2.AppendLine(netInterfaceInfo.InterfaceName);
sb2.Append("网络接口状态: ");
sb2.AppendLine(netInterfaceInfo.InterfaceState.ToString());
sb2.Append("网络接口类型: ");
sb2.AppendLine(netInterfaceInfo.InterfaceType.ToString());
sb2.Append("网络接口子类型: ");
sb2.AppendLine(netInterfaceInfo.InterfaceSubtype.ToString());
Dispatcher.BeginInvoke(() => textblock3.Text = sb2.ToString());
});
socket.ConnectAsync(socketEventArg);

base.OnNavigatedTo(e);
}
private void Button_Click_1(object sender, RoutedEventArgs e)
{
NavigationService.Navigate(new Uri("/Page1.xaml", UriKind.Relative));
}

3. 检测网络状态改变
　　手机的网络连接并不如电脑稳定，当你到信号不好的地方，或者自动连接上WiFi等情况，怎么通过代码自动监测呢，下面演示了当手机网络改变时，列举出日志清单，并实时刷新网络信息。

[XAML]


   

































































[C#]


    public partial class Page1 : PhoneApplicationPage
{
public ObservableCollection Changes { get; set; }
public ObservableCollection NetworkInterfaces { get; set; }
public Page1()
{
InitializeComponent();

// 网络可用性改变事件日志
Changes = new ObservableCollection();
lbNetworkChanges.DataContext = Changes;
//当前可用的网络接口
NetworkInterfaces = new ObservableCollection();
lbNetworkInterfaces.DataContext = NetworkInterfaces;
//网络可用性改变时
DeviceNetworkInformation.NetworkAvailabilityChanged += new EventHandler(ChangeDetected);
UpdateNetworkInterfaces();
UpdateNetworkStatus();
}
void ChangeDetected(object sender, NetworkNotificationEventArgs e)
{
string change = string.Empty;
switch (e.NotificationType)
{
case NetworkNotificationType.InterfaceConnected:
change = "连接: ";
break;
case NetworkNotificationType.InterfaceDisconnected:
change = "断开: ";
break;
case NetworkNotificationType.CharacteristicUpdate:
change = "变更: ";
break;
default:
change = "未知: ";
break;
}
string changeInformation = String.Format(" {0} {1} {2} ({3})",
DateTime.Now.ToShortTimeString(), change, e.NetworkInterface.InterfaceName,
InterfaceTypeConvert.Convert(e.NetworkInterface.InterfaceType) + "," + InterfaceTypeConvert.ConvertSub(e.NetworkInterface.InterfaceSubtype));
Dispatcher.BeginInvoke(() =>
{
Changes.Add(changeInformation);
UpdateNetworkStatus();
UpdateNetworkInterfaces();
});
}
//更新网络接口
private void UpdateNetworkInterfaces()
{
NetworkInterfaces.Clear();
//获取网络接口列表
NetworkInterfaceList networkInterfaceList = new NetworkInterfaceList();
foreach (NetworkInterfaceInfo networkInterfaceInfo in networkInterfaceList)
{
NetworkInterfaces.Add(String.Format("{0} ({1},{2})",
networkInterfaceInfo.InterfaceName,
InterfaceTypeConvert.Convert(networkInterfaceInfo.InterfaceType),
InterfaceTypeConvert.ConvertSub(networkInterfaceInfo.InterfaceSubtype)));
}
}
//更新网络状态
private void UpdateNetworkStatus()
{
tbIsCellularDataEnabled.Text = (DeviceNetworkInformation.IsCellularDataEnabled) ? "是" : "否";
tbIsNetworkAvailable.Text = (DeviceNetworkInformation.IsNetworkAvailable) ? "是" : "否";
tbIsWiFiEnabled.Text = (DeviceNetworkInformation.IsWiFiEnabled) ? "是" : "否";
}
//连接设置
private void Button_Click_3(object sender, RoutedEventArgs e)
{
var settringTypeString = string.Empty;
var button = sender as Button;
if (button != null) settringTypeString = Convert.ToString(button.Content);
var settringType = ConnectionSettingsType.WiFi;
switch (settringTypeString)
{
case "飞行": settringType = ConnectionSettingsType.AirplaneMode;
break;
case "网络": settringType = ConnectionSettingsType.Cellular;
break;
case "蓝牙": settringType = ConnectionSettingsType.Bluetooth;
break;
default: break;
}
//连接设置选择框
ConnectionSettingsTask connectionSettings = new ConnectionSettingsTask();
// 连接设置的类型
connectionSettings.ConnectionSettingsType = settringType;
connectionSettings.Show();
}
//刷新
private void Button_Click_2(object sender, RoutedEventArgs e)
{
UpdateNetworkStatus();
UpdateNetworkInterfaces();
Changes.Clear();
}
private void Button_Click_1(object sender, RoutedEventArgs e)
{
NavigationService.Navigate(new Uri("/MainPage.xaml", UriKind.Relative));
}
}

　　

五、访问web的几种方式
　　Windows phone中访问Internet的方式主要有：通过套接字、WebClient 类、HttpWebRequest 类、服务引用等。套接字我们已经讲过。我主要讲解后面三种。
　　WebClient 类：一般用于通过访问URL获取特定的资源，下面是使用方法：

[C#]


WebClient webClient = new WebClient();
webClient.DownloadStringAsync(new Uri("http://www.baidu.com", UriKind.Absolute));
webClient.DownloadStringCompleted += (a, b) =>
{
if (b.Error == null && !b.Cancelled)
{
Dispatcher.BeginInvoke(() => MessageBox.Show(b.Result));
}
};

　　HttpWebRequest 类：对http做了基本的实现，相当于比直接用socket方便一点。

[C#]


Uri uri = new Uri("http://192.168.100.212");
HttpWebRequest httpWebRequest = (HttpWebRequest)WebRequest.Create(uri);
httpWebRequest.Method = "POST";
//异步获取HTTP请求正文流
httpWebRequest.BeginGetRequestStream(new AsyncCallback(a =>
{
var httpWebRequest2 = a.AsyncState as HttpWebRequest;
var stream = httpWebRequest2.EndGetRequestStream(a);
var streamWriter = new StreamWriter(stream);
//在HTTP请求正文流中写入要POST的参数
streamWriter.WriteLine("wd=111");
streamWriter.Close();
//开始异步的向远程主机发送HTTP请求
httpWebRequest2.BeginGetResponse(new AsyncCallback(b =>
{
try
{
var httpWebRequest3 = b.AsyncState as HttpWebRequest;
//请求执行完成，得到HTTP相应
WebResponse webResponse = httpWebRequest3.EndGetResponse(b);
var s = webResponse.ContentType;
//获取到HTTP相应正文流
var stream3 = webResponse.GetResponseStream();
//读出来，转换成字符串
var streamReader = new StreamReader(stream3, Encoding.UTF8);
var text = streamReader.ReadToEnd();
Dispatcher.BeginInvoke(() => MessageBox.Show(text));
}
catch (Exception ex)
{
var c = ex.Message;
}
}), httpWebRequest2);
}), httpWebRequest);

　　服务引用：其实于一般的服务引用一样，只不过这里只支持异步实现。

[C#]


//添加服务引用后，下面代码为异步调用web服务
ServiceReference1.WebService1SoapClient c = new ServiceReference1.WebService1SoapClient();
c.HelloWorldAsync("");
c.HelloWorldCompleted += (a, b) =>
{
Dispatcher.BeginInvoke(() => MessageBox.Show(b.Result));
};

　　


作者：[Lipan]
出处：[http://www.iyunv.com/lipan/]
版权声明：本文的版权归作者与博客园共有。转载时须注明原文出处以及作者，并保留原文指向型链接，不得更改原文内容。否则作者将保留追究其法律责任。


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