IChartFormat DoughnutHoleSize Property

<para>//Create worksheet</para><para>Workbook workbook = new Workbook();</para><para>workbook.LoadFromFile("Sample.xlsx");</para><para>Worksheet worksheet = workbook.Worksheets[0];</para><para>//Create chart and set range</para><para>IChart chart = worksheet.Charts.Add();</para><para>chart.DataRange = worksheet.Range["A1:C2"];</para><para>//Set chart type</para><para>chart.ChartType = ExcelChartType.Doughnut;</para><para>//Set chart format</para><para>IChartFormat format = chart.Series[0].Format.Options;</para><para>//Set Doughnut hole size</para><para>format.DoughnutHoleSize = 60;</para><para>//Save to file</para><para>workbook.SaveToFile("Chart.xlsx");</para>