WPF调用Python心率监测脚本解决方案

一、项目背景

你有一个Python脚本PolarHR.py，使用bleak库异步扫描并连接蓝牙心率设备，后台线程持续获取心率数据，并每2秒打印最新心率。

你希望在WPF程序中启动该Python脚本，实时获取心率数据并显示。

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二、Python脚本（PolarHR.py）

请确保Python脚本内容如下，重点是：

• 使用print(..., flush=True)确保输出不被缓冲，WPF能及时读取。
• 每2秒打印格式为当前心率: 数字的字符串，方便WPF解析。

import asyncio
import threading
from bleak import BleakScanner, BleakClient
import timeHR_UUID = "00002a37-0000-1000-8000-00805f9b34fb"
_latest_heart_rate = None
_lock = threading.Lock()async def _heart_rate_worker():global _latest_heart_rateprint("开始扫描设备...", flush=True)devices = await BleakScanner.discover(timeout=5)print(f"扫描到设备数量: {len(devices)}", flush=True)polar_devices = [d for d in devices if d.name and "Polar" in d.name]print(f"找到 Polar 设备数量: {len(polar_devices)}", flush=True)if not polar_devices:print("未找到 Polar 设备", flush=True)returndevice = polar_devices[0]async with BleakClient(device.address) as client:queue = asyncio.Queue()def callback(sender, data):flags = data[0]hr_format = flags & 0x01if hr_format:hr = int.from_bytes(data[1:3], byteorder='little')else:hr = data[1]queue.put_nowait(hr)await client.start_notify(HR_UUID, callback)print(f"已连接设备 {device.name}，开始接收心率数据...", flush=True)while True:hr = await queue.get()with _lock:_latest_heart_rate = hrdef _start_loop(loop):asyncio.set_event_loop(loop)loop.run_until_complete(_heart_rate_worker())def start_heart_rate_monitor():loop = asyncio.new_event_loop()t = threading.Thread(target=_start_loop, args=(loop,), daemon=True)t.start()def get_latest_heart_rate():with _lock:return _latest_heart_rateif __name__ == "__main__":start_heart_rate_monitor()while True:hr = get_latest_heart_rate()if hr is not None:print(f"当前心率: {hr}", flush=True)else:print("当前心率: None", flush=True)time.sleep(2)

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三、WPF项目代码示例

1. MainWindow.xaml

<Window x:Class="HeartRateWpfApp.MainWindow"xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"Title="心率监测" Height="200" Width="300"><Grid><TextBlock x:Name="HeartRateTextBlock" FontSize="24" HorizontalAlignment="Center" VerticalAlignment="Center"/></Grid>
</Window>

2. MainWindow.xaml.cs

using System;
using System.Diagnostics;
using System.Text.RegularExpressions;
using System.Windows;
using System.Windows.Threading;namespace HeartRateWpfApp
{public partial class MainWindow : Window{private Process _pythonProcess;private string _latestHeartRate = null;private DispatcherTimer _timer;public MainWindow(){InitializeComponent();StartPythonProcess();StartTimer();}private void StartPythonProcess(){var psi = new ProcessStartInfo{FileName = @"C:\Path\To\Your\Python\python.exe",  // 替换为你的python.exe完整路径Arguments = "-u PolarHR.py",  // -u 禁用缓冲，PolarHR.py是脚本名WorkingDirectory = @"C:\Users\86730\Desktop\步态资料\步态资料", // 脚本所在目录UseShellExecute = false,RedirectStandardOutput = true,RedirectStandardError = true,CreateNoWindow = true};_pythonProcess = new Process();_pythonProcess.StartInfo = psi;_pythonProcess.OutputDataReceived += PythonOutputDataReceived;_pythonProcess.ErrorDataReceived += PythonErrorDataReceived;_pythonProcess.Start();_pythonProcess.BeginOutputReadLine();_pythonProcess.BeginErrorReadLine();}private void PythonOutputDataReceived(object sender, DataReceivedEventArgs e){if (string.IsNullOrEmpty(e.Data)) return;// 调试输出，方便查看Python打印内容Console.WriteLine("Python STDOUT: " + e.Data);// 匹配格式：当前心率: 数字var match = Regex.Match(e.Data, @"当前心率:\s*(\d+)");if (match.Success){_latestHeartRate = match.Groups[1].Value;}}private void PythonErrorDataReceived(object sender, DataReceivedEventArgs e){if (!string.IsNullOrEmpty(e.Data)){Console.WriteLine("Python STDERR: " + e.Data);}}private void StartTimer(){_timer = new DispatcherTimer();_timer.Interval = TimeSpan.FromSeconds(2);_timer.Tick += Timer_Tick;_timer.Start();}private void Timer_Tick(object sender, EventArgs e){if (string.IsNullOrEmpty(_latestHeartRate)){HeartRateTextBlock.Text = "等待心率数据...";}else{HeartRateTextBlock.Text = $"当前心率: {_latestHeartRate}";}}protected override void OnClosed(EventArgs e){base.OnClosed(e);if (_pythonProcess != null && !_pythonProcess.HasExited){_pythonProcess.Kill();_pythonProcess.Dispose();}}}
}

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四、注意事项

1. 替换Python路径
   将FileName中的路径替换为你本机Python解释器的完整路径，例如：

   C:\Users\86730\AppData\Local\Programs\Python\Python310\python.exe
   

2. 确保Python环境安装依赖
   确保bleak库已安装：

   C:\Path\To\Your\Python\python.exe -m pip install bleak
   

3. 确保Python脚本路径正确
   WorkingDirectory设置为Python脚本所在目录，Arguments只写脚本名。

4. 调试输出
   运行WPF程序时，查看输出窗口（Console）是否有Python的标准输出和错误输出，确认Python脚本是否正常启动。

5. 蓝牙权限
   确保WPF程序有权限访问蓝牙设备，必要时以管理员身份运行。

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五、总结

• Python脚本后台线程持续采集心率数据，主线程每2秒打印格式为当前心率: 数字的字符串。
• WPF启动Python进程，异步读取标准输出，使用正则表达式匹配并提取数字心率。
• WPF用DispatcherTimer每2秒刷新UI显示最新心率。