不显示MSChart x轴标签

我目前正在构建一个应用程序，显示一个线形图，并使用MSChartControl。

相关代码如下:

WeatherDatabase _db = new WeatherDatabase(Properties.Settings.Default.SqlConnectionString);
    private void AddSensorDataToGraph(int sensorType, string xTitle, string yTitle, string Title)
    {
        var sensorIdList = (from d in _db.Sensors where d.TypeId == sensorType select d.Id).ToArray();
        var startDate = dateTimePickerStart.Value;
        var stopDate = dateTimePickerStop.Value;
        SetMaxMinValues(dateTimePickerStart.Value.ToOADate(), dateTimePickerStop.Value.ToOADate());
        this.Text = chartValues.Titles["Titel"].Text = String.Format("{0} vom {1} bis {2}", Title, startDate, stopDate);
        chartValues.ChartAreas[CHARTAREA].AxisX.Title = xTitle;
        chartValues.ChartAreas[CHARTAREA].AxisY.Title = yTitle;
        // Alte Datensätze löschen
        chartValues.Series.Clear();
        foreach (var sensorId in sensorIdList)
        {
            var values = (from d in _db.DeviceIO where d.IdSensor == sensorId && d.Timestamp > startDate && d.Timestamp < stopDate orderby d.Timestamp ascending select d).ToArray();
            if (values.Length > 0)
            {
                var desc = values[0].Sensors.SensorType.Description;
                chartValues.Series.Add(GenerateDefaultSeries(String.Format("{0}'r'nSensorId: {1}", desc, sensorId)));
                //chartValues.Series.Add("Test" + sensorId);
                int seriesId = chartValues.Series.Count - 1;
                foreach (var item in values)
                {
                    if (item.Value == null)
                    {
                        continue;
                    }
                    if ((double)item.Value == NOVALUE)
                    {
                        continue;
                    }
                    AddPointToChart((DateTime)item.Timestamp, (double)item.Value, seriesId);
                }
            }
        }
    }
    private void AddPointToChart(DateTime timestamp, double value, int series)
    {
        DataPoint dataPoint = chartValues.Series[series].Points.Add(value);
        dataPoint.XValue = timestamp.ToOADate();
        dataPoint.AxisLabel = "dd.MM.yy hh:mm";
    }
    private void SetMaxMinValues(double min, double max)
    {
        if (min < max)
        {
            chartValues.ChartAreas[CHARTAREA].AxisX.Minimum = min;
            chartValues.ChartAreas[CHARTAREA].AxisX.Maximum = max;
        }
    }
    private Series GenerateDefaultSeries(string Name)
    {
        // Grundeinstellungen für die Data-Series setzen
        Series series = new Series();
        series.ChartType = SeriesChartType.Line;
        series.Name = Name;
        series.IsValueShownAsLabel = false;
        series.IsVisibleInLegend = true;
        series.IsXValueIndexed = false;
        series.AxisLabel = "dd.MM.yy hh:mm";
        // series.LabelFormat = "g";
        series.XAxisType = AxisType.Primary;
        series.XValueType = ChartValueType.Auto;
        series.YValuesPerPoint = 1;
        //    series.AxisLabel = "dd.MM.yy hh:mm";
        return series;
    }

如果在设计器模式下添加一个系列，则x轴标签正确点击查看图片
但如果我启动我的应用程序并以编程方式添加一个系列它看起来像这样

有人知道为什么x轴标题/标签没有正确显示吗?

编辑:基于Tom的帮助，我改变了一些东西:

var seriesName = String.Format("{0}'r'nSensorId: {1}", desc, sensorId);
                var curSeries = chartValues.Series.Add(seriesName);
                UpdateSeriesSettings(ref curSeries);
              [...]
     AddPointToChart((DateTime)item.Timestamp, (double)item.Value, curSeries);

[…]

private void UpdateSeriesSettings(ref Series series)
{
    // Grundeinstellungen für die Data-Series setzen
    // Series series = new Series();
    series.ChartType = SeriesChartType.Spline;
    series.IsValueShownAsLabel = false;
    series.IsVisibleInLegend = true;
    series.IsXValueIndexed = false;
    series.AxisLabel = "dd.MM.yy hh:mm";
    // series.LabelFormat = "g";
    series.XAxisType = AxisType.Primary;
    series.XValueType = ChartValueType.Auto;
    series.YValuesPerPoint = 1;
    //    series.AxisLabel = "dd.MM.yy hh:mm";
}

但是我的X轴仍然没有标签):

使用了以下代码:

修复我的问题。

var desc = values[0].Sensors.SensorType.Description;
var seriesName = String.Format("{0}'r'nSensorId: {1}", desc, sensorId);
curSeries = chartValues.Series.Add(seriesName);
curSeries.ChartType = SeriesChartType.Line;
curSeries.XValueType = ChartValueType.DateTime;
foreach (var item in values)
{
    curSeries.Points.AddXY(item.Timestamp, item.Value);
}