how to write bold text in excel c# win forms

Question

I use this code and want to make bold latter on heading please help me.

want to create designed excel sheet that looking good after export. in other ways that modified but want to use this way to modified excel sheet.

StreamWriter wr = new StreamWriter(@"D:\\test.xls");


foreach (string sHeader in Header)
{
      wr.Write(sHeader);
      wr.WriteLine();
}
wr.Write("");
wr.WriteLine();

for (int i = 0; i < Dt.Columns.Count; i++)
{
      wr.Write(Dt.Columns[i].ToString().ToUpper() + "\t");
}

wr.WriteLine();

//write rows to excel file
for (int i = 0; i < (Dt.Rows.Count); i++)
{
     for (int j = 0; j < Dt.Columns.Count; j++)
     {
            if (Dt.Rows[i][j] != null)
            {
                wr.Write(Convert.ToString(Dt.Rows[i][j]) + "\t");
            }
            else
            {
                wr.Write("\t");
            }
      }
      //go to next line
      wr.WriteLine();
}
//close file
wr.Close();

Answer 1

add this reference and try this "using Microsoft.Office.Interop.Excel.ApplicationClass"

 try
    {
        SaveFileDialog sfd = new SaveFileDialog();
        sfd.FileName = "Total Expiry Inventories Data ";
        sfd.DefaultExt = "xls";
        sfd.Filter = "xlsx files(*.xlsx)|*.xlsx";
        if (sfd.ShowDialog() != System.Windows.Forms.DialogResult.OK)
        {
            return;
        }

        Excel.Application ExcelApp = new Excel.Application();
        Excel.Workbook workbook = ExcelApp.Workbooks.Add(Excel.XlWBATemplate.xlWBATWorksheet);
        Excel.Worksheet worksheet1 = (Excel.Worksheet)workbook.Worksheets[1];
        worksheet1.Name = "Expiry Data";
        for (int i = 1; i < GrdViewData.Columns.Count + 1; i++)
        {
            worksheet1.Cells[1, i] = GrdViewData.Columns[i - 1].HeaderText;
            worksheet1.Cells[1, i].Font.Bold = true;


        }
        for (int i = 0; i < GrdViewData.Rows.Count; i++)
        {
            for (int j = 0; j < GrdViewData.Columns.Count; j++)
            {
                worksheet1.Cells[i + 2, j + 1] = GrdViewData.Rows[i].Cells[j].Value.ToString();
            }
        }
        worksheet1.Rows.Font.Size = 12;
        //  Excel.Range range_Consolidated = worksheet1.Rows.get_Range("a1", "d1");
        // range_Consolidated.Font.Bold = true;

        // range_Consolidated.Font.Italic = true;

        string ExcelFileName = sfd.FileName;
        workbook.SaveAs(ExcelFileName);
        workbook.Close(false, ExcelFileName, Missing.Value);
        ExcelApp.Quit();

        ExcelApp = null;
        GC.Collect();
        GC.WaitForPendingFinalizers();
        MessageBox.Show("File Saved! you can open it from\n  '" + sfd.FileName + "'", "EXPORT", MessageBoxButtons.OK, MessageBoxIcon.Information);
    }

    catch (Exception ex)
    {
        MessageBox.Show(ex.Message);
    }
    finally
    {
    }