1.首先是要在界面程序中枚举出蓝牙设备

2.为使用蓝牙设备的相关信息创建解锁用的Windows Hello设备

3.当task收到解锁事件的时候再次枚举蓝牙设备,然后判断每个枚举到的蓝牙设备有没有对应Windows Hello设备

4. 有就使用使用这个Windows Hello设备解锁电脑

那这样我先使用我的小米手环的信息创建对应的解锁设备,当我的手环在附近的时候Task就能枚举到它从而解锁,当手环不在附近的时候Task自然就枚举不到它,于是就不能使用Windows Hello解锁。

关于枚举蓝牙设备,我又在微软的官方例子中找到了Demo

Demo地址: https://github.com/Microsoft/Windows-universal-samples/tree/master/Samples/DeviceEnumerationAndPairing

这个Demo就展示了使用DeviceWatch去枚举设备

DeviceWatcher m_deviceWatcher;
string[] requestedProperties = { "System.Devices.Aep.DeviceAddress", "System.Devices.Aep.IsConnected" };
m_deviceWatcher = DeviceInformation.CreateWatcher("(System.Devices.Aep.ProtocolId:=\"{bb7bb05e-5972-42b5-94fc-76eaa7084d49}\")",
//m_deviceWatcher = DeviceInformation.CreateWatcher("(System.Devices.Aep.ProtocolId:=\"{e0cbf06c-cd8b-4647-bb8a-263b43f0f974}\")",
                                                  requestedProperties,
                                                  DeviceInformationKind.AssociationEndpoint);
m_deviceWatcher.Added += DeviceWatcher_Added;
m_deviceWatcher.Updated += DeviceWatcher_Updated;
m_deviceWatcher.Removed += DeviceWatcher_Removed;
m_deviceWatcher.EnumerationCompleted += DeviceWatcher_EnumerationCompleted;
m_deviceWatcher.Stopped += DeviceWatcher_Stopped;
m_deviceWatcher.Start();

这个代码应该是一目了然的, 其中的关键就在于CreateWatcher时候使用的参数 {bb7bb05e-5972-42b5-94fc-76eaa7084d49} 能枚举到小米手环但是枚举不到手机, {e0cbf06c-cd8b-4647-bb8a-263b43f0f974} 则相反能枚举到手机但是枚举不到小米手环。

这个类还能枚举到其他很多的设备,就靠CreateWatcher的参数具体可以看官方的Demo。

下面是接口的定义,其中 DeviceInformation 和 DeviceInformationUpdate 就包含了设备的信息

private void DeviceWatcher_Added(DeviceWatcher Sender, DeviceInformation DeviceInfo)
private void DeviceWatcher_Updated(DeviceWatcher Sender, DeviceInformationUpdate DeviceInfoUpdate)
private void DeviceWatcher_Removed(DeviceWatcher Sender, DeviceInformationUpdate DeviceInfoUpdate)
private void DeviceWatcher_EnumerationCompleted(DeviceWatcher Sender, object e)
private void DeviceWatcher_Stopped(DeviceWatcher Sender, object e)

 基本属性都有对应的变量,而我在CreateWatcher的时候附加的属性  string[] requestedProperties = { "System.Devices.Aep.DeviceAddress", "System.Devices.Aep.IsConnected" }; 会以键值对的形式保存在 DeviceInformation 和 DeviceInformationUpdate 的 Properties中

 我在界面程序中使用这套接口枚举到了我的手环,基本信息是这样的

DeviceID: BluetoothLE#BluetoothLExx:xx:xx:xx:xx:xx-xx:xx:xx:xx:xx:xx

Name: MI Band 2

 一开始我是想直接使用 BluetoothLE#BluetoothLExx:xx:xx:xx:xx:xx-xx:xx:xx:xx:xx:xx 这个ID去创建解锁设备的,但是发现都失败,实验下来可能是只能使用GUID去创建解锁设备。于是我就需要把 BluetoothLE#BluetoothLExx:xx:xx:xx:xx:xx-xx:xx:xx:xx:xx:xx 也存储起来,存储的思路

其实例子中也给出了,就是存在解锁设备的  DeviceConfigurationData  中,因为 我还要在 DeviceConfigurationData 中存储解锁用的两个密码,所以我干脆就将在 DeviceConfigurationData  中存储JSON格式的数据,专门写了个序列化很反序列化的类。

public class JsonData
    public string Sign { get; set; }
    public string DeviceID { get; set; }
    public string DeviceKey { get; set; }
    public string AuthKey { get; set; }
    public bool CanUnLock { get; set; }
public class CMyHelloWinJson
    public static JsonData ParesToData(string js)
        JsonData rv = null;
            JsonObject schoolObject = JsonObject.Parse(js);
            if (schoolObject != null)
                rv = new JsonData();
                rv.Sign = schoolObject.GetNamedString("Sign");
                rv.DeviceID = schoolObject.GetNamedString("DeviceID");
                rv.DeviceKey = schoolObject.GetNamedString("DeviceKey");
                rv.AuthKey = schoolObject.GetNamedString("AuthKey");
                rv.CanUnLock = schoolObject.GetNamedBoolean("CanUnLock");
        }catch(Exception e)
            return rv;
        return rv;
    public static string ParesToJson(JsonData Dat)
        JsonObject schoolObject = new JsonObject();
        schoolObject.SetNamedValue("Sign", JsonValue.CreateStringValue(Dat.Sign));
        schoolObject.SetNamedValue("DeviceID", JsonValue.CreateStringValue(Dat.DeviceID));
        schoolObject.SetNamedValue("DeviceKey", JsonValue.CreateStringValue(Dat.DeviceKey));
        schoolObject.SetNamedValue("AuthKey", JsonValue.CreateStringValue(Dat.AuthKey));
        schoolObject.SetNamedValue("CanUnLock", JsonValue.CreateBooleanValue(Dat.CanUnLock));
        return schoolObject.ToString();

 所以在界面中创建解锁设备的代码就变成了这样

string modelnumber = "MyHelloWin";
// 随机数转 string 可能会丢失信息的
byte[] deviceKeyArray = new byte[32];
byte[] authKeyArray = new byte[32];
IBuffer deviceKey = CryptographicBuffer.CreateFromByteArray(deviceKeyArray);
IBuffer authKey = CryptographicBuffer.CreateFromByteArray(authKeyArray);
JsonData Dat = new JsonData();
Dat.Sign = "MyHellowin";
Dat.DeviceKey = System.Text.Encoding.UTF8.GetString(deviceKeyArray);
Dat.AuthKey = System.Text.Encoding.UTF8.GetString(authKeyArray);
Dat.DeviceID = DeviceID;
Dat.CanUnLock = false;
string js = CMyHelloWinJson.ParesToJson(Dat);
byte[] signArry = System.Text.Encoding.UTF8.GetBytes(js);
IBuffer deviceConfigData = CryptographicBuffer.CreateFromByteArray(signArry);
String deviceGUId = System.Guid.NewGuid().ToString();
int state = await WinHello.RegisterDeviceAsync(deviceGUId, bleDeviceDisplay.DeviceName, modelnumber, deviceConfigData, deviceKey, authKey);
// 注册
SecondaryAuthenticationFactorDeviceCapabilities Capabilities = SecondaryAuthenticationFactorDeviceCapabilities.SecureStorage;
SecondaryAuthenticationFactorRegistrationResult RegistrationResult = await SecondaryAuthenticationFactorRegistration.RequestStartRegisteringDeviceAsync(DervicesID,
        Capabilities,
        FriendlyName,
        ModelNumber,
        deviceKey,
        authKey);
if (RegistrationResult.Status == SecondaryAuthenticationFactorRegistrationStatus.Started) {
    await RegistrationResult.Registration.FinishRegisteringDeviceAsync(DerviceContext);
return (int)RegistrationResult.Status;

 界面写好了,那么解锁的时候思路大致就是这样的

先是枚举出所有的蓝牙设备,使用和上面相同的方法。

private void DeviceWatcher_Added(DeviceWatcher Sender, DeviceInformation DeviceInfo)
{

  IReadOnlyList<SecondaryAuthenticationFactorInfo> deviceList = await SecondaryAuthenticationFactorRegistration.FindAllRegisteredDeviceInfoAsync(SecondaryAuthenticationFactorDeviceFindScope.AllUsers);
  for (int i = 0; i < deviceList.Count; i++)
      SecondaryAuthenticationFactorInfo deviceInfo = deviceList.ElementAt(i);
      byte[] combinedDataArray;
      CryptographicBuffer.CopyToByteArray(deviceInfo.DeviceConfigurationData, out combinedDataArray);
      string JS = System.Text.Encoding.UTF8.GetString(combinedDataArray);
      JsonData Dat = CMyHelloWinJson.ParesToData(JS);
      if (Dat == null)
          continue;
      if (String.Equals(Dat.DeviceID, DeviceInfo.DeviceID)) { // 使用这个设备进行解锁  } 
  }
}

具体解锁的方法,上面一篇文章中有相应的介绍。或者你直接看我写的Demo: http://git.oschina.net/alwaysking/MyHelloWin

然而,当我天真的这样就搞定的时候,来了个晴天霹雳,因为在Task中使用DeviceWatcher枚举设备的时候他的回调函数根本不会被触发。注意我的蓝牙设备是配对的设备。

解决方法也是有的,我们下一篇再讲