如何在C#中将ppt转换为HTML？

using Microsoft.Office.Core;
using Microsoft.Office.Interop.PowerPoint;

public void ConvertPptToHtml(string pptFilePath, string htmlFilePath)
{
    Application pptApplication = new Application();
    Presentation pptPresentation = pptApplication.Presentations.Open(pptFilePath, MsoTriState.msoFalse, MsoTriState.msoFalse, MsoTriState.msoFalse);
    pptPresentation.SaveAs(htmlFilePath, PpSaveAsFileType.ppSaveAsHTML, MsoTriState.msoFalse);
    pptPresentation.Close();
    pptApplication.Quit();
}