Question

I have a graph (x y graph) with several curves on it in an excel file.
How can i access this graph in a c# application and extract values from the graph?

As an example, given curve 1 and an x value on an excel graph, i want to get the y value on the corresponding curve using a c# windows application.
is this possible?

Answer 1

You can use EPPlus and get excel range for chart series and then from range you get Chart data, something like this :

private List<double> ExtractChartValues(FileInfo excelFile, string sheetName, int drawing, int chartSerie)
{
  ExcelPackage ePack = new ExcelPackage(excelFile);
  ExcelWorksheet ws = ePack.Workbook.Worksheets[sheetName];

  List<double> result = new List<double>();
  ExcelChart ec = (ExcelChart)ws.Drawings[drawing];
  ExcelRange dataRange = ws.Cells[ec.Series[chartSerie].Series];
  foreach (ExcelRangeBase data in dataRange)
  {
    if (data.Value != null)
      result.Add((double)data.Value);
  }
  return result;
}