从 UWP 获取 TCP 服务器上的实时数据(更新)
Get the live data on TCP server from UWP (UPDATED)
下面是一种基本上将数据发送到 TCP 服务器的方法。
UPDATE BEGINS HERE:
//////////////////////////////////
private string FormatValueByPresentation(IBuffer buffer, GattPresentationFormat format)
{
// BT_Code: For the purpose of this sample, this function converts only UInt32 and
// UTF-8 buffers to readable text. It can be extended to support other formats if your app needs them.
byte[] data;
CryptographicBuffer.CopyToByteArray(buffer, out data);
if (format != null)
{
if (format.FormatType == GattPresentationFormatTypes.UInt32 && data.Length >= 4)
{
return BitConverter.ToInt32(data, 0).ToString();
}
else if (format.FormatType == GattPresentationFormatTypes.Utf8)
{
try
{
return Encoding.UTF8.GetString(data);
}
catch (ArgumentException)
{
return "(error: Invalid UTF-8 string)";
}
}
else
{
// Add support for other format types as needed.
return "Unsupported format: " + CryptographicBuffer.EncodeToHexString(buffer);
}
}
else if (data != null)
{
// We don't know what format to use. Let's try some well-known profiles, or default back to UTF-8.
if (selectedCharacteristic.Uuid.Equals(GattCharacteristicUuids.HeartRateMeasurement))
{
try
{
///////LOOK HERE/////
**string b = ParseHeartRateValue(data).ToString();
TrySend(b);
//return "Heart Rate: " + ParseHeartRateValue(data).ToString();
return "Heart Rate: " + b;**
}
catch (ArgumentException)
{
return "Heart Rate: (unable to parse)";
}
}
else if (selectedCharacteristic.Uuid.Equals(GattCharacteristicUuids.BatteryLevel))
{
try
{
// battery level is encoded as a percentage value in the first byte according to
// https://www.bluetooth.com/specifications/gatt/viewer?attributeXmlFile=org.bluetooth.characteristic.battery_level.xml
return "Battery Level: " + data[0].ToString() + "%";
}
catch (ArgumentException)
{
return "Battery Level: (unable to parse)";
}
}
// This is our custom calc service Result UUID. Format it like an Int
else if (selectedCharacteristic.Uuid.Equals(Constants.ResultCharacteristicUuid))
{
return BitConverter.ToInt32(data, 0).ToString();
}
// No guarantees on if a characteristic is registered for notifications.
else if (registeredCharacteristic != null)
{
// This is our custom calc service Result UUID. Format it like an Int
if (registeredCharacteristic.Uuid.Equals(Constants.ResultCharacteristicUuid))
{
return BitConverter.ToInt32(data, 0).ToString();
}
}
else
{
try
{
return "Unknown format: " + Encoding.UTF8.GetString(data);
}
catch (ArgumentException)
{
return "Unknown format";
}
}
}
else
{
return "Empty data received";
}
return "Unknown format";
}
///////// END OF UPDATE //////
private async void TrySend(string data)
{
// Create the StreamSocket and establish a connection to the echo server.
StreamSocket socket = new StreamSocket();
try
{
var streamSocket = new Windows.Networking.Sockets.StreamSocket();
{
//The server hostname that we will be establishing a connection to. In this example, the server and client are in the same process.
var hostName = new Windows.Networking.HostName("127.0.0.1");
await streamSocket.ConnectAsync((new Windows.Networking.HostName("127.0.0.1")), "9999");
// Send a request to the echo server.
using (Stream outputStream = streamSocket.OutputStream.AsStreamForWrite())
{
using (var streamWriter = new StreamWriter(outputStream))
{
while (true)
{
await streamWriter.WriteLineAsync(data);
await streamWriter.FlushAsync();
}
//await streamWriter.WriteLineAsync(data);
//await streamWriter.FlushAsync();
}
}
}
}
catch (Exception)
{
}
}
这是我接收数据的 TCP 服务器代码:
public class EchoServer {
public static void Main() {
TcpListener listener = null;
try
{
listener = new TcpListener(IPAddress.Parse("127.0.0.1"), 9999);
listener.Start();
Console.WriteLine("TCP Server Has Started....");
while (true)
{
Console.WriteLine(" ");
Console.WriteLine("Waiting for incoming client connections....");
Console.WriteLine(" ");
Console.WriteLine("A message will display below once the client starts and establishes a connection ");
TcpClient client = listener.AcceptTcpClient();
Console.WriteLine(" ");
Console.WriteLine("Okay, Accepting Client connection now");
Console.WriteLine(" ");
Console.WriteLine("Accepted new client connection.....");
StreamReader reader = new StreamReader(client.GetStream());
StreamWriter writer = new StreamWriter(client.GetStream());
string s = string.Empty;
while (!(s = reader.ReadLine()).Equals("Exit") || (s == null)) {
Console.WriteLine("From client -> " + s);
writer.WriteLine("From server -> " + s);
writer.Flush();
}
reader.Close();
writer.Close();
client.Close();
}
} catch (Exception e)
{
Console.WriteLine(e);
} finally
{
if (listener != null)
{
listener.Stop();
}
}
}
}
现在,我要获取的数据是心率,它每两秒变化一次。然而,在 TCP 服务器上,我只获得了心率的第一个记录值,并且它不断重复而不是获得新的值。
我在 Whosebug 上看到了类似的 post:
有人建议使用我在代码中看到的 while 循环。
关于我该怎么做,还有其他建议吗?
谢谢
while (true)
{
await streamWriter.WriteLineAsync(data);
await streamWriter.FlushAsync();
}
while(true) 将不断重复,这意味着它将始终以其当前值发送 'data'。这就是导致您出现问题的原因。
在我看来,您应该在 'TrySend' 方法之外保持与 TCP 服务器的连接打开,并且仅使用此方法发送数据。这样你就不需要使用这个循环了。
编辑:
试试这个:
private async void CharacteristicReadButton_Click()
{
while(true)
{
// BT_Code: Read the actual value from the device by using Uncached.
GattReadResult result = await selectedCharacteristic.ReadValueAsync(BluetoothCacheMode.Uncached);
if (result.Status == GattCommunicationStatus.Success)
{
string formattedResult = FormatValueByPresentation(result.Value, presentationFormat);
rootPage.NotifyUser($"Read result: {formattedResult}", NotifyType.StatusMessage);
//string formattedResult = FormatValueByPresentation(result.Value, presentationFormat);
//rootPage.NotifyUser($"Read result: {formattedResult}", NotifyType.StatusMessage);
}
else
{
rootPage.NotifyUser($"Read failed: {result.Status}", NotifyType.ErrorMessage);
}
}
}
下面是一种基本上将数据发送到 TCP 服务器的方法。
UPDATE BEGINS HERE:
//////////////////////////////////
private string FormatValueByPresentation(IBuffer buffer, GattPresentationFormat format)
{
// BT_Code: For the purpose of this sample, this function converts only UInt32 and
// UTF-8 buffers to readable text. It can be extended to support other formats if your app needs them.
byte[] data;
CryptographicBuffer.CopyToByteArray(buffer, out data);
if (format != null)
{
if (format.FormatType == GattPresentationFormatTypes.UInt32 && data.Length >= 4)
{
return BitConverter.ToInt32(data, 0).ToString();
}
else if (format.FormatType == GattPresentationFormatTypes.Utf8)
{
try
{
return Encoding.UTF8.GetString(data);
}
catch (ArgumentException)
{
return "(error: Invalid UTF-8 string)";
}
}
else
{
// Add support for other format types as needed.
return "Unsupported format: " + CryptographicBuffer.EncodeToHexString(buffer);
}
}
else if (data != null)
{
// We don't know what format to use. Let's try some well-known profiles, or default back to UTF-8.
if (selectedCharacteristic.Uuid.Equals(GattCharacteristicUuids.HeartRateMeasurement))
{
try
{
///////LOOK HERE/////
**string b = ParseHeartRateValue(data).ToString();
TrySend(b);
//return "Heart Rate: " + ParseHeartRateValue(data).ToString();
return "Heart Rate: " + b;**
}
catch (ArgumentException)
{
return "Heart Rate: (unable to parse)";
}
}
else if (selectedCharacteristic.Uuid.Equals(GattCharacteristicUuids.BatteryLevel))
{
try
{
// battery level is encoded as a percentage value in the first byte according to
// https://www.bluetooth.com/specifications/gatt/viewer?attributeXmlFile=org.bluetooth.characteristic.battery_level.xml
return "Battery Level: " + data[0].ToString() + "%";
}
catch (ArgumentException)
{
return "Battery Level: (unable to parse)";
}
}
// This is our custom calc service Result UUID. Format it like an Int
else if (selectedCharacteristic.Uuid.Equals(Constants.ResultCharacteristicUuid))
{
return BitConverter.ToInt32(data, 0).ToString();
}
// No guarantees on if a characteristic is registered for notifications.
else if (registeredCharacteristic != null)
{
// This is our custom calc service Result UUID. Format it like an Int
if (registeredCharacteristic.Uuid.Equals(Constants.ResultCharacteristicUuid))
{
return BitConverter.ToInt32(data, 0).ToString();
}
}
else
{
try
{
return "Unknown format: " + Encoding.UTF8.GetString(data);
}
catch (ArgumentException)
{
return "Unknown format";
}
}
}
else
{
return "Empty data received";
}
return "Unknown format";
}
///////// END OF UPDATE //////
private async void TrySend(string data)
{
// Create the StreamSocket and establish a connection to the echo server.
StreamSocket socket = new StreamSocket();
try
{
var streamSocket = new Windows.Networking.Sockets.StreamSocket();
{
//The server hostname that we will be establishing a connection to. In this example, the server and client are in the same process.
var hostName = new Windows.Networking.HostName("127.0.0.1");
await streamSocket.ConnectAsync((new Windows.Networking.HostName("127.0.0.1")), "9999");
// Send a request to the echo server.
using (Stream outputStream = streamSocket.OutputStream.AsStreamForWrite())
{
using (var streamWriter = new StreamWriter(outputStream))
{
while (true)
{
await streamWriter.WriteLineAsync(data);
await streamWriter.FlushAsync();
}
//await streamWriter.WriteLineAsync(data);
//await streamWriter.FlushAsync();
}
}
}
}
catch (Exception)
{
}
}
这是我接收数据的 TCP 服务器代码:
public class EchoServer {
public static void Main() {
TcpListener listener = null;
try
{
listener = new TcpListener(IPAddress.Parse("127.0.0.1"), 9999);
listener.Start();
Console.WriteLine("TCP Server Has Started....");
while (true)
{
Console.WriteLine(" ");
Console.WriteLine("Waiting for incoming client connections....");
Console.WriteLine(" ");
Console.WriteLine("A message will display below once the client starts and establishes a connection ");
TcpClient client = listener.AcceptTcpClient();
Console.WriteLine(" ");
Console.WriteLine("Okay, Accepting Client connection now");
Console.WriteLine(" ");
Console.WriteLine("Accepted new client connection.....");
StreamReader reader = new StreamReader(client.GetStream());
StreamWriter writer = new StreamWriter(client.GetStream());
string s = string.Empty;
while (!(s = reader.ReadLine()).Equals("Exit") || (s == null)) {
Console.WriteLine("From client -> " + s);
writer.WriteLine("From server -> " + s);
writer.Flush();
}
reader.Close();
writer.Close();
client.Close();
}
} catch (Exception e)
{
Console.WriteLine(e);
} finally
{
if (listener != null)
{
listener.Stop();
}
}
}
}
现在,我要获取的数据是心率,它每两秒变化一次。然而,在 TCP 服务器上,我只获得了心率的第一个记录值,并且它不断重复而不是获得新的值。
我在 Whosebug 上看到了类似的 post:
有人建议使用我在代码中看到的 while 循环。 关于我该怎么做,还有其他建议吗?
谢谢
while (true)
{
await streamWriter.WriteLineAsync(data);
await streamWriter.FlushAsync();
}
while(true) 将不断重复,这意味着它将始终以其当前值发送 'data'。这就是导致您出现问题的原因。
在我看来,您应该在 'TrySend' 方法之外保持与 TCP 服务器的连接打开,并且仅使用此方法发送数据。这样你就不需要使用这个循环了。
编辑:
试试这个:
private async void CharacteristicReadButton_Click()
{
while(true)
{
// BT_Code: Read the actual value from the device by using Uncached.
GattReadResult result = await selectedCharacteristic.ReadValueAsync(BluetoothCacheMode.Uncached);
if (result.Status == GattCommunicationStatus.Success)
{
string formattedResult = FormatValueByPresentation(result.Value, presentationFormat);
rootPage.NotifyUser($"Read result: {formattedResult}", NotifyType.StatusMessage);
//string formattedResult = FormatValueByPresentation(result.Value, presentationFormat);
//rootPage.NotifyUser($"Read result: {formattedResult}", NotifyType.StatusMessage);
}
else
{
rootPage.NotifyUser($"Read failed: {result.Status}", NotifyType.ErrorMessage);
}
}
}