private void Init()
{
    //加载心率模拟数据
    using StreamReader reader = new("fhrdata.txt");
    string line;
    while ((line = reader.ReadLine()) != null)
    {
        fhrDatas.Add(int.Parse(line));
    }

    //定时器模拟后台定时推送心率数据
    pushFhrDataTimer = new DispatcherTimer
    {
        Interval = TimeSpan.FromSeconds(1),
    };
    pushFhrDataTimer.Tick += PushFhrDataTimer_Tick;
    pushFhrDataTimer.Start();
}

private void PushFhrDataTimer_Tick(object sender, EventArgs e)
{
    //一秒钟推送4个数据
    var fhrs = new FhrModel[4];

    for (int i = 0; i < fhrs.Length; i++)
    {
        fhrs[i] = new FhrModel
        {
            Index = timeIndex,
            Fhr1 = fhrDatas[dataIndex],
            Fhr2 = fhrDatas[dataIndex],
            Fhr3 = fhrDatas[dataIndex],
        };

        timeIndex++;
        dataIndex++;
        if (dataIndex >= fhrDatas.Count) dataIndex = 0;
    }

    //推送数据到心率曲线控件
    chart.AddFhrData(fhrs);
}