Workbook.ExportToHtmlAsync(String, Worksheet) Method
Asynchronously exports the specified worksheet to the specified file in HTML format.
A String value which contains the full path (including the file name and extension) specifying where the HTML file will be created.
A Worksheet object to be exported to HTML.
An Task object representing an asynchronous export operation.
Take into account the following when you call this method:
The events fired by this method call may occur in a different thread than the target operation.
The operation is not thread safe (the document should not be accessed simultaneously by different threads). Wait until the operation is completed before you continue to work with the document (for example, use the
Calculate Formulas Before Export
The default calculation mode for a Workbook is Manual. This mode implies that the Spreadsheet does not recalculate formulas before it generates an HTML file. Call the Workbook.Calculate or Workbook.CalculateFull method to calculate all formulas in the workbook before you export it to HTML.