Using C# to SaveAs Excel 2007 and up

Question

I included this:

using Excel = Microsoft.Office.Interop.Excel;

I would like to be able to open an Excel file XLSX and do a save it as a different file:

    xlWorkBook.SaveAs(xlWorkBook.Path + @"\XMLCopy.xls",
                      Excel.XlFileFormat.xlXMLSpreadsheet,
                      ,,
                      false,
                      false,
                      Excel.XlSaveAsAccessMode.xlNoChange,
                      ,,,,);

There are missing parameters above, and I do not understand what to enter for them!

Here's my full code:

Excel.Application xlApp;
            Excel.Workbook xlWorkBook;
            Excel.Worksheet xlWorkSheet;
            Excel.Range range;

            string str;
            int rCnt = 0;
            int cCnt = 0;

            xlApp = new Excel.ApplicationClass();
            xlWorkBook = xlApp.Workbooks.Open("csharp.net-informations.xls", 0, true, 5, "", "", true, Microsoft.Office.Interop.Excel.XlPlatform.xlWindows, "\t", false, false, 0, true, 1, 0);
            xlWorkSheet = (Excel.Worksheet)xlWorkBook.Worksheets.get_Item(1);

Question : How can I save the Excel file with a different name/path using c# as above?

Answer 1

You need to use Visual Studios 2010 to properly use optional parameters in C#.

If you cannot use Visual Studios 2010 then Eddy's suggestion Type.Missing should work.

When using methods with optional parameters (and not using Type.Missing) it is usually a good idea to use named parameters when calling the function.

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Also, you should be aware of the limitations and quirks of optional parameters (though most of them should not affect you since you are not creating methods with optional parameters):

• http://www.grumpydev.com/2010/04/19/optional-parameters-in-c4-c3-and-vb-net-with-a-side-order-of-il-quirks/
• http://geekswithblogs.net/BlackRabbitCoder/archive/2010/06/17/c-optional-parameters---pros-and-pitfalls.aspx
• http://lostechies.com/jimmybogard/2010/05/18/caveats-of-c-4-0-optional-parameters/

It should be noted that I do not recommend creating methods with optional parameters. Either overload the method or create a new object where the user can set the object properties before calling the method.