IExportObjectListener interface

Allows users to manipulate objects while exporting.

public interface IExportObjectListener


Name Description
ExportObject(ExportObjectEvent) Export one object.


The following example creates a Workbook, opens a file named designer.xls in it and makes the horizontal and vertical scroll bars invisible for the Workbook. It then replaces two string values with an Integer value and string value respectively within the spreadsheet and finally sends the updated file to the client browser.

    //custom implementation of IExportObjectListener
    class CustomExportObjectListener : IExportObjectListener
        private int imgIdx = 0;
        public object ExportObject(ExportObjectEvent e)
            Object source = e.GetSource();
            if (source is Shape)
                Shape shape = (Shape)source;
                string url = null;
                switch (shape.MsoDrawingType)
                    case MsoDrawingType.Picture:
                        url = SaveImage(((Picture)shape).Data, imgIdx, ((Picture)shape).ImageFormat);
                if (url != null)
                return url;
            return null;
        private string SaveImage(byte[] data, int imgIdx, ImageFormat format)
            //here save the image to any location, then return the url(relative or absolute) that the generated html can get the image
            return "temp1/temp2.png";
     //Save html file with custom listener
        HtmlSaveOptions saveOptions = new HtmlSaveOptions();
        saveOptions.ExportObjectListener = new CustomExportObjectListener();
        Stream stream = File.Create(outfn);
        book.Save(stream, saveOptions);

See Also