Excel Open XML Error: "find unreadable content" when creating a simple example

Question

I get the ambiguous "excel found notreadable content" error when I try to open a document created using the following code:

public void GenerateWorkbookFromDB()
{
    //Make a copy of the template file
    File.Copy(HttpContext.Current.Server.MapPath("ReportTemplate/test.xlsx"), HttpContext.Current.Server.MapPath("Reports/test.xlsx"), true);

    //Open up the copied template workbook
    using (SpreadsheetDocument myWorkbook = SpreadsheetDocument.Open(HttpContext.Current.Server.MapPath("Reports/test.xlsx"), true))
    {
        WorkbookPart workbookPart = myWorkbook.WorkbookPart;
        WorksheetPart worksheetPart = workbookPart.WorksheetParts.First();
        string origninalSheetId = workbookPart.GetIdOfPart(worksheetPart);

        WorksheetPart replacementPart = workbookPart.AddNewPart<WorksheetPart>();
        string replacementPartId = workbookPart.GetIdOfPart(replacementPart);

        OpenXmlReader reader = OpenXmlReader.Create(worksheetPart);
        OpenXmlWriter writer = OpenXmlWriter.Create(replacementPart);

        Row r = new Row();
        Cell c = new Cell();
        CellValue v = new CellValue();
        v.Text = "test";
        c.Append(v);

        while (reader.Read())
        {
            if (reader.ElementType == typeof(SheetData))
            {
                if (reader.IsEndElement)
                    continue;
                writer.WriteStartElement(new SheetData());

                for (int row = 0; row < 20; row++)
                {
                    writer.WriteStartElement(r);

                    for (int col = 0; col < 4; col++)
                    {
                        writer.WriteElement(c);
                    }

                    writer.WriteEndElement();
                }

                writer.WriteEndElement();
            }
            else
            {
                if (reader.IsStartElement)
                    writer.WriteStartElement(reader);
                else if (reader.IsEndElement)
                    writer.WriteEndElement();
            }
        }
        reader.Close();
        writer.Close();

        try
        {
            Sheet sheet = workbookPart.Workbook.Descendants<Sheet>().Where(s => s.Id.Value.Equals(origninalSheetId)).First();
            sheet.Id.Value = replacementPartId;
            workbookPart.DeletePart(worksheetPart);
        }
        catch (Exception ex) { }
    }
}

any help or suggestions much appreciated !: D

Answer 1

I really found a way to fix the error by changing the way text was entered into the cell. Pay attention to the code below, where I commented out 2 lines and that I replaced them.

public void GenerateWorkbookFromDB()
{
    //Make a copy of the template file
    File.Copy(HttpContext.Current.Server.MapPath("ReportTemplate/test.xlsx"), HttpContext.Current.Server.MapPath("Reports/test.xlsx"), true);

    //Open up the copied template workbook
    using (SpreadsheetDocument myWorkbook = SpreadsheetDocument.Open(HttpContext.Current.Server.MapPath("Reports/test.xlsx"), true))
    {
        WorkbookPart workbookPart = myWorkbook.WorkbookPart;
        WorksheetPart worksheetPart = workbookPart.WorksheetParts.First();
        string origninalSheetId = workbookPart.GetIdOfPart(worksheetPart);

        WorksheetPart replacementPart = workbookPart.AddNewPart<WorksheetPart>();
        string replacementPartId = workbookPart.GetIdOfPart(replacementPart);

        OpenXmlReader reader = OpenXmlReader.Create(worksheetPart);
        OpenXmlWriter writer = OpenXmlWriter.Create(replacementPart);

        Row r = new Row();
        Cell c = new Cell();
        string txt = "test";
        c.CellValue = new CellValue(txt.ToString());
        c.DataType = new EnumValue<CellValues>(CellValues.String);
        //v.Text = "test";
        //c.Append(v);

        while (reader.Read())
        {
            if (reader.ElementType == typeof(SheetData))
            {
                if (reader.IsEndElement)
                    continue;
                writer.WriteStartElement(new SheetData());

                for (int row = 0; row < 20; row++)
                {
                    writer.WriteStartElement(r);

                    for (int col = 0; col < 4; col++)
                    {
                        writer.WriteElement(c);
                    }

                    writer.WriteEndElement();
                }

                writer.WriteEndElement();
            }
            else
            {
                if (reader.IsStartElement)
                    writer.WriteStartElement(reader);
                else if (reader.IsEndElement)
                    writer.WriteEndElement();
            }
        }
        reader.Close();
        writer.Close();

        try
        {
            Sheet sheet = workbookPart.Workbook.Descendants<Sheet>().Where(s => s.Id.Value.Equals(origninalSheetId)).First();
            sheet.Id.Value = replacementPartId;
            workbookPart.DeletePart(worksheetPart);
        }
        catch (Exception ex) { }
    }
}

I hope this helps anyone who may be experiencing the same problem or something like that.

Thanks to those who tried to answer; -)

Answer 2

, -.

, .

Excel 31 . , , 31 , .

Answer 3

, , Cell , . , . A2, B2, C2... Z2, AA2, AB2. : , AA2 A2 B2, , .

Answer 4

, Cell. , : Numerics Strings.

 public static void WriteValueOnCell(Cell cell, object value)
    {
        var sValue = value = x.ToString();
        var isValueNumeric = value.GetType().IsNumeric();
        cell.DataType = (isValueNumeric)? CellValues.Number : CellValues.String;
        cell.CellValue = new CellValue(sValue);
    }
    //This example uses this Helper. It informs if an object type is Numeric ;-)
    public static class TypeHelper
    {
        private static readonly HashSet<Type> NumericTypes = new HashSet<Type>
        {
            typeof(int),  typeof(double),  typeof(decimal),
            typeof(long), typeof(short),   typeof(sbyte),
            typeof(byte), typeof(ulong),   typeof(ushort),
            typeof(uint), typeof(float)
        };

        public static bool IsNumeric(this Type myType)
        {
            return NumericTypes.Contains(Nullable.GetUnderlyingType(myType) ?? myType);
        }
    }

Answer 5

- , ? '<' ' > '? , XML, . , , HTTPUtility.HTMLEncode?

Answer 6

web.config.

maxRequestLength executeTimeout, !

System.Web, :

httpRuntime requestValidationMode="2.0" maxRequestLength="1048576" executionTimeout="600"

, .

Answer 7

I had this problem, and after using the SDK tool, I found that CellValues.Date was not really supported. If you are trying to format your cells to have the appropriate DataType, and you get this message, try leaving your date cells as CellValues.String.