Set Rows to repeat at top when printing - Open XML and Excel

I am trying to get the first 4 rows of an xlsx file to repeat at the top of each page when printed. I am using the Open XML SDK to accomplish this.

My file is being generated by the SSRS execution web service as a filestream. I then need to modify several layout and page settings (margins, page size, zoom, etc) before delivering the file to the user, as my users have very little Excel acumen. All other settings I need to tweak are working correctly, so I have stripped out all of that code from this example.

When trying to set the repeating page headers using the code below, it executes with no errors. However, when I try to open the file after executing the code, I am getting a corrupt file message and it won't open.

Any idea what I'm doing wrong here?! It's driving me crazy!

using (SpreadsheetDocument xl = SpreadsheetDocument.Open("C:\\" + filename, true))
{
WorkbookPart wbp = xl.WorkbookPart;

//-----------------------------------------
// repeat rows at top when printing
//-----------------------------------------
DefinedNames dn = new DefinedNames();
wbp.Workbook.Append(dn);
wbp.Workbook.Save();

DefinedNames definedNames = wbp.Workbook.Descendants<DefinedNames>().FirstOrDefault();
DefinedName n1 = new DefinedName() { Name = "_xlnm.Print_Titles", LocalSheetId = (UInt32Value)0U };
n1.Text = "alpha_sort_nc!$1:$4";
definedNames.Append(n1);
wbp.Workbook.Save();

xl.Close();
}

Solution

Update: @Duncan - After your comment, I try to find out root cause of file corrupt. It turns to be SpreadsheetPinterSettings is binary data in the document. Even adding the DefinedName _xlnm.Print_Titles to Spreadsheet; it doesn't have any effect during a Print/Print Preview.

It seems Open XML approach for handling spreadsheet printer settings is not helpful.

Reflect code from Open XML SDK Productivity tool: manually created Print Titles in MS Excel

// Adds child parts and generates content of the specified part.
public void CreateSpreadsheetPrinterSettingsPart(SpreadsheetPrinterSettingsPart part)
{
    GeneratePartContent(part);

}

// Generates content of part.
private void GeneratePartContent(SpreadsheetPrinterSettingsPart part)
{
    System.IO.Stream data = GetBinaryDataStream(partData);
    part.FeedData(data);
    data.Close();
}

#region Binary Data
private string partData = "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";

private System.IO.Stream GetBinaryDataStream(string base64String)
{
    return new System.IO.MemoryStream(System.Convert.FromBase64String(base64String));
}

#endregion

Alternate Approach [I'm not sure, you're interested :)]: to due binary data part, code snippet for same using Interop. works perfectly!

Excel.Application xlApp = new Excel.Application();
Excel._Workbook xlWorkbook = xlApp.Workbooks.Open(@"C:/Users/jeeva/sample-excel-files/SampleExcel.xlsx");
Excel._Worksheet xlWorksheet = xlWorkbook.Sheets[1];

xlWorksheet.PageSetup.PrintTitleRows = "$1:$1";

xlWorkbook.Save();
xlWorkbook.Close();

Previous One:

These three lines not nesscary.

DefinedNames dn = new DefinedNames();
wbp.Workbook.Append(dn);
wbp.Workbook.Save();

To set Print Titles, DefinedName Text should be in format of "Worksheet_name!Row_Range or Column_Range".
For example: Row range: Worksheet1!$1:$1 and Column range: Worksheet1!$A:$A

using (SpreadsheetDocument xl = SpreadsheetDocument.Open(@"C:/Users/jeeva/sample-excel-files/SampleExcel.xlsx", true))
{             
    WorkbookPart wbp = xl.WorkbookPart;

    // Input for this program
    string name = "_xlnm.Print_Titles";
    string comment = "this is Print Titles for Sheet1";
    string text = "Sheet1!$1:$1";

    if (wbp.Workbook.DefinedNames == null) 
    {
        wbp.Workbook.DefinedNames = new DefinedNames();
    }                

    bool bFound = false;
    foreach (DefinedName d in wbp.Workbook.DefinedNames)
    {
        // if found overwrite existing defined name
        if (d.Name.Value.Equals(name, StringComparison.InvariantCultureIgnoreCase)) 
        {
            bFound = true;
            d.Text = text;
            d.Comment = comment;
            break;
        }
    }

    if (!bFound) // if not found, add one
    {
        wbp.Workbook.DefinedNames.Append(getDefinedName(name, text, comment));
    }

    wbp.Workbook.Save();
    xl.Close();
}

private static DefinedName getDefinedName(string Name, string Text, string Comment)
{
    DefinedName dn = new DefinedName();
    dn.Text = Text;
    dn.Name = Name;
    dn.Comment = Comment;
    dn.LocalSheetId = (UInt32Value)1U;
    dn.Xlm = true; // since its a special schema name
}