Format an Excel column (or cell) as Text in C#?

Question

I am losing the leading zeros when I copy values from a datatable to an Excel sheet. That's because probably Excel treats the values as a number instead of text.

I created the worksheet in C# and I am copying the values like so:

myWorksheet.Cells[i + 2, j] = dtCustomers.Rows[i][j - 1].ToString();

How do I format a whole column or each cell as Text? A related question, how to cast myWorksheet.Cells[i + 2, j] to show a style property in Intellisense?

Answer 1

//where [1] - column number which you want to make text

ExcelWorksheet.Columns[1].NumberFormat = "@";


//If you want to format a particular column in all sheets in a workbook - use below code. Remove loop for single sheet along with slight changes.

  //path were excel file is kept


     string ResultsFilePath = @"C:\\Users\\krakhil\\Desktop\\TGUW EXCEL\\TEST";

            Excel.Application ExcelApp = new Excel.Application();
            Excel.Workbook ExcelWorkbook = ExcelApp.Workbooks.Open(ResultsFilePath);
            ExcelApp.Visible = true;

            //Looping through all available sheets
            foreach (Excel.Worksheet ExcelWorksheet in ExcelWorkbook.Sheets)
            {                
                //Selecting the worksheet where we want to perform action
                ExcelWorksheet.Select(Type.Missing);
                ExcelWorksheet.Columns[1].NumberFormat = "@";
            }

            //saving excel file using Interop
            ExcelWorkbook.Save();

            //closing file and releasing resources
            ExcelWorkbook.Close(Type.Missing, Type.Missing, Type.Missing);
            Marshal.FinalReleaseComObject(ExcelWorkbook);
            ExcelApp.Quit();
            Marshal.FinalReleaseComObject(ExcelApp);

Answer 2

Before your write to Excel need to change the format:

xlApp = New Excel.Application
xlWorkSheet = xlWorkBook.Sheets("Sheet1")

Dim cells As Excel.Range = xlWorkSheet.Cells

'set each cell's format to Text
cells.NumberFormat = "@"

'reset horizontal alignment to the right
cells.HorizontalAlignment = Excel.XlHAlign.xlHAlignRight

Answer 3

Solution that worked for me for Excel Interop:

myWorksheet.Columns[j].NumberFormat = "@";      // column as a text
myWorksheet.Cells[i + 2, j].NumberFormat = "@"; // cell as a text

This code should run before putting data to Excel. Column and row numbers are 1-based.

A bit more details. Whereas accepted response with reference for SpreadsheetGear looks almost correct, I had two concerns about it:

1. I am not using SpreadsheetGear. I was interested in regular Excel communication thru Excel interop without any 3rdparty libraries,
2. I was searching for the way to format column by number, not using ranges like "A:A".

Answer 4

Below is some code to format columns A and C as text in SpreadsheetGear for .NET which has an API which is similar to Excel - except for the fact that SpreadsheetGear is frequently more strongly typed. It should not be too hard to figure out how to convert this to work with Excel / COM:

IWorkbook workbook = Factory.GetWorkbook();
IRange cells = workbook.Worksheets[0].Cells;
// Format column A as text.
cells["A:A"].NumberFormat = "@";
// Set A2 to text with a leading '0'.
cells["A2"].Value = "01234567890123456789";
// Format column C as text (SpreadsheetGear uses 0 based indexes - Excel uses 1 based indexes).
cells[0, 2].EntireColumn.NumberFormat = "@";
// Set C3 to text with a leading '0'.
cells[2, 2].Value = "01234567890123456789";
workbook.SaveAs(@"c:\tmp\TextFormat.xlsx", FileFormat.OpenXMLWorkbook);

Disclaimer: I own SpreadsheetGear LLC

Answer 5

If you set the cell formatting to Text prior to adding a numeric value with a leading zero, the leading zero is retained without having to skew results by adding an apostrophe. If you try and manually add a leading zero value to a default sheet in Excel and then convert it to text, the leading zero is removed. If you convert the cell to Text first, then add your value, it is fine. Same principle applies when doing it programatically.

        // Pull in all the cells of the worksheet
        Range cells = xlWorkBook.Worksheets[1].Cells;
        // set each cell's format to Text
        cells.NumberFormat = "@";
        // reset horizontal alignment to the right
        cells.HorizontalAlignment = XlHAlign.xlHAlignRight;

        // now add values to the worksheet
        for (i = 0; i <= dataGridView1.RowCount - 1; i++)
        {
            for (j = 0; j <= dataGridView1.ColumnCount - 1; j++)
            {
                DataGridViewCell cell = dataGridView1[j, i];
                xlWorkSheet.Cells[i + 1, j + 1] = cell.Value.ToString();
            }
        }

Answer 6

I know this question is aged, still, I would like to contribute.

Applying Range.NumberFormat = "@" just partially solve the problem:

• Yes, if you place the focus on a cell of the range, you will read text in the format menu
• Yes, it align the data to the left
• But if you use the type formula to check the type of the value in the cell, it will return 1 meaning number

Applying the apostroph behave better. It sets the format to text, it align data to left and if you check the format of the value in the cell using the type formula, it will return 2 meaning text