OpenXML SDK Inject VBA into excel workbook

Based on my research there isn't a way to insert the project part data in a format that you can manipulate in C#. In the OpenXML format, the VBA project is still stored in a binary format. However, copying the VbaProjectPart from one Excel document into another should work. As a result, you'd have to determine what you wanted the project part to say in advance.

If you are OK with this, then you can add the following code to a template Excel file in the 'ThisWorkbook' Microsoft Excel Object, along with the appropriate Macro code:

Private Sub Workbook_Open()    Run "Module1.SomeMacroName()"End Sub

To copy the VbaProjectPart object from one file to the other, you would use code like this:

public static void InsertVbaPart(){    using(SpreadsheetDocument ssDoc = SpreadsheetDocument.Open("file1.xlsm", false))    {        WorkbookPart wbPart = ssDoc.WorkbookPart;        MemoryStream ms;        CopyStream(ssDoc.WorkbookPart.VbaProjectPart.GetStream(), ms);        using(SpreadsheetDocument ssDoc2 = SpreadsheetDocument.Open("file2.xlsm", true))        {            Stream stream = ssDoc2.WorkbookPart.VbaProjectPart.GetStream();            ms.WriteTo(stream);        }    }}public static void CopyStream(Stream input, Stream output){    byte[] buffer = new byte[short.MaxValue + 1];    while (true)    {        int read = input.Read(buffer, 0, buffer.Length);        if (read <= 0)            return;        output.Write(buffer, 0, read);    }}

Hope that helps.

I found that the other answers still resulted in the duplicate "Worksheet" object. I used a similar solution to what @ZlotaMoneta said, but with a different syntax found here:

List<VbaProjectPart> newParts = new List<VbaProjectPart>();using (var originalDocument = SpreadsheetDocument.Open("file1.xlsm"), false)){    newParts = originalDocument.WorkbookPart.GetPartsOfType<VbaProjectPart>().ToList();    using (var document = SpreadsheetDocument.Open("file2.xlsm", true))    {        document.WorkbookPart.DeleteParts(document.WorkbookPart.GetPartsOfType<VbaProjectPart>());        foreach (var part in newParts)        {            VbaProjectPart vbaProjectPart = document.WorkbookPart.AddNewPart<VbaProjectPart>();            using (Stream data = part.GetStream())            {                vbaProjectPart.FeedData(data);            }                            }        //Note this prevents the duplicate worksheet issue        spreadsheetDocument.WorkbookPart.Workbook.WorkbookProperties.CodeName = "ThisWorkbook";    }}

You need to specify "codeName" attribute in the "xl/workbook..xml" objectAfter feeding the VbaProjectPart with macro. Add this code:

var workbookPr = spreadsheetDocument.WorkbookPart.Workbook.Descendants<WorkbookProperties>().FirstOrDefault();workbookPr.CodeName = "ThisWorkBook";

After opening the file everything should work now.

So, to add macro you need to:

1. Change document type to macro enabled

2. Add VbaProjectPart and feed it with earlier created macro

3. Add workbookPr codeName attr in xl/workbook..xml with value "ThisWorkBook"

4. Save as with .xlsm ext.