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ChartSeries series = new ChartSeries("series1", ChartSeriesType.Gantt);
for (int i = 0; i < dTable.Rows.Count; i++)
series.Points.Add(i, Convert.ToDateTime(dTable.Rows[i]["StartDate"]), Convert.ToDateTime(dTable.Rows[i]["EndDate"]));
this.chart.PrimaryXAxis.ValueType = ChartValueType.DateTime;