Add CSV file data as WorkSheet to an Excel file using C# in ASP.Net

Hi vygi0913,

I have created sample that full-fill your requirement.

Code

protected void Page_Load(object sender, EventArgs e)
{
    int i = 0;
    DataTable dt = new DataTable();
    dt.Columns.Add("SourceFile");
    dt.Columns.Add("DestinationFile");
    dt.Columns.Add("Result");
    string result = "Passed";
    foreach (var line in File.ReadAllLines(Server.MapPath("CSVs/Compare.csv")))
    {
        string sourceFilePath = line.Split(';')[0].Split(',')[0];
        string destinationFilePath = line.Split(';')[0].Split(',')[1];
        var sourceFile = File.ReadAllLines(sourceFilePath);
        var destinationFile = File.ReadAllLines(destinationFilePath);
        var compareFile = from ln in sourceFile
                            from ln1 in destinationFile
                            where ln != ln1
                            select ln;
        if (compareFile.ToList().Count > 0)
        {
            result = "Failed";
        }
        dt.Rows.Add(sourceFilePath, destinationFilePath, result);
        i++;
    }

    Microsoft.Office.Interop.Excel.Application excel = default(Microsoft.Office.Interop.Excel.Application);
    Microsoft.Office.Interop.Excel.Workbook workBook = default(Microsoft.Office.Interop.Excel.Workbook);
    excel = new Microsoft.Office.Interop.Excel.Application();
    excel.Visible = true;
    workBook = excel.Workbooks.Open(Server.MapPath("~/CSVs/Book1.xls"));
    var excelSheets = workBook.Sheets as Microsoft.Office.Interop.Excel.Sheets;
    var excelNewSheet = (Microsoft.Office.Interop.Excel.Worksheet)excelSheets.Add(excelSheets[excelSheets.Count], Type.Missing, Type.Missing, Type.Missing);
    excelNewSheet.Name = string.Format("{0}_{1}", DateTime.Now.ToShortDateString(), DateTime.Now.ToLongTimeString()).Replace("/", "_").Replace(":", "_");
    int irow = 1;
    int col = 1;
    foreach (DataColumn column in dt.Columns)
    {
        excelNewSheet.Cells[irow, col] = column.ColumnName;
        col++;
    }
    foreach (DataRow dr in dt.Rows)
    {
        irow += 1;
        col = 0;
        foreach (string c in dr.ItemArray)
        {
            col += 1;
            excelNewSheet.Cells[irow, col] = c;
        }
    }
    workBook.Save();
    workBook.Close();
    excel.Visible = true;
    excel.UserControl = true;
    excelNewSheet = null;
    workBook = null;
    excel = null;
}

Sceernshot