C#, Write XLSX using OpenXmlWriter and Open XML SDK

c#, export-to-excel, openxml-sdk

Solution

I don't understand this well enough yet, but I got it working. Here's what I ended up with.

class Program
{
    static void Main(string[] args)
    {
        File.Copy("book.xlsx", "output.xlsx", true);
        WriteRandomValuesSAX("output.xlsx", 10, 10);
    }

    static void WriteRandomValuesSAX(string filename, int numRows, int numCols)
    {
        using (SpreadsheetDocument myDoc = SpreadsheetDocument.Open(filename, true))
        {
            WorkbookPart workbookPart = myDoc.WorkbookPart;
            WorksheetPart worksheetPart = workbookPart.WorksheetParts.Last();

            OpenXmlWriter writer = OpenXmlWriter.Create(worksheetPart);

            Row r = new Row();
            Cell c = new Cell();
            CellValue v = new CellValue("Test");
            c.AppendChild(v);

            writer.WriteStartElement(new Worksheet());
            writer.WriteStartElement(new SheetData());
            for (int row = 0; row < numRows; row++)
            {
                writer.WriteStartElement(r);
                for (int col = 0; col < numCols; col++)
                {
                    writer.WriteElement(c);
                }
                writer.WriteEndElement();
            }
            writer.WriteEndElement();
            writer.WriteEndElement();

            writer.Close();
        }
    }
}

Notice I added `writer.WriteStartElement(new Worksheet());` and another `writer.WriteEndElement();`

I found the correct xml format here: http://msdn.microsoft.com/en-us/library/gg278309.aspx

Which is

<?xml version="1.0" encoding="utf-8"?> <x:worksheet xmlns:x="http://schemas.openxmlformats.org/spreadsheetml/2006/main">
    <x:sheetData>
        <x:row r="1">
            <x:c r="A1" t="n">
                <x:v>100</x:v>
            </x:c>
        </x:row>
    </x:sheetData> </x:worksheet>

So I opened (unzipped) the xlsx file and navigated to output.xlsx\xl\worksheets\sheet1.xml and saw that I was missing the `<x:worksheet>`.

Problem

In C#, the following program compiles and runs, but it doesn't write anything in the excel output file. I got it working without the `OpenXmlWriter` but I started running out of memory so I have to switch to the `OpenXmlWriter` according to this http://blogs.msdn.com/b/brian_jones/archive/2010/06/22/writing-large-excel-files-with-the-open-xml-sdk.aspx ``` class Program { static void Main(string[] args) { File.Copy("book.xlsx", "output.xlsx", true); WriteValuesSAX("output.xlsx", 10, 10); } static void WriteValuesSAX(string filename, int numRows, int numCols) { using (SpreadsheetDocument myDoc = SpreadsheetDocument.Open(filename, true)) { WorkbookPart workbookPart = myDoc.WorkbookPart; WorksheetPart worksheetPart = workbookPart.WorksheetParts.First(); OpenXmlWriter writer = OpenXmlWriter.Create(worksheetPart); Row r = new Row(); Cell c = new Cell(); CellValue v = new CellValue("Test"); c.AppendChild(v); writer.WriteStartElement(new SheetData()); for (int row = 0; row < numRows; row++) { writer.WriteStartElement(r); for (int col = 0; col < numCols; col++) { writer.WriteElement(c); } writer.WriteEndElement(); } writer.WriteEndElement(); writer.Close(); } } } ``` Why doesn't it write anything to output?

Original source