MsChart:如何在X轴上显示日历周数作为标签？

Question

我需要在像"CW21","CW22"这样的MSChart中格式化时间轴的标签,...我正在努力一段时间,但还没有找到任何解决方案.

1. 有一个LabelStyle.Format属性,但这不支持(AFAIK)日历周.它使用DateTime格式字符串.有没有办法引入自定义格式化程序？

2. 在框架中我找到了Calendar.GetWeekOfYear方法,它将为我提供正确的周数.现在的问题是如何将这些结合在一起？

有没有什么好的策略可以通用方式在轴上设置自己的标签？(事先不知道轴的最小/最大点)

Answer 1

是的,您可以使用Chart.FormatNumber事件,例如:

private void FillChart()
{
    // register the format event
    this.chart1.FormatNumber += new EventHandler<FormatNumberEventArgs>(chart1_FormatNumber);

    // fill the data table with values
    DataTable dt = new DataTable();
    dt.Columns.Add("X", typeof(DateTime));
    dt.Columns.Add("Y", typeof(double));

    dt.Rows.Add(DateTime.Today.AddDays(1), 10);
    dt.Rows.Add(DateTime.Today.AddDays(8), 30);
    dt.Rows.Add(DateTime.Today.AddDays(15), 10);
    dt.Rows.Add(DateTime.Today.AddDays(21), 20);
    dt.Rows.Add(DateTime.Today.AddDays(25), 40);
    dt.Rows.Add(DateTime.Today.AddDays(31), 25);

    // bind the data table to chart
    this.chart1.Series.Clear();

    var series = this.chart1.Series.Add("Series 1");
    series.XValueMember = "X";
    series.YValueMembers = "Y";

    series.ChartType = SeriesChartType.Line;
    this.chart1.DataSource = dt;
    this.chart1.DataBind();

    // set a custom format to recognize the AxisX label in the event handler
    this.chart1.ChartAreas[0].AxisX.LabelStyle.Format = "CustomAxisXFormat"; 

}

void chart1_FormatNumber(object sender, FormatNumberEventArgs e)
{
    if (e.ElementType == ChartElementType.AxisLabels &&
        e.Format == "CustomAxisXFormat")
    {
        if (e.ValueType == ChartValueType.DateTime)
        {
            var currentCalendar = CultureInfo.CurrentCulture.Calendar;
            e.LocalizedValue = "CW" +
                currentCalendar.GetWeekOfYear(DateTime.FromOADate(e.Value),
                System.Globalization.CalendarWeekRule.FirstDay,
                CultureInfo.CurrentCulture.DateTimeFormat.FirstDayOfWeek);
        }
    }
}

这是结果: