在excel中将值从标签放到列的简短或简单的解决方案

大家好，任何人都可以帮我解决这个问题，我这里有一个代码，可以计算从B列到AF列的水果数量（31天）我使用的开关是从第1种情况到第31种情况。我希望我的代码是简单的或循环的。31个病例太长了。顺便说一下，我的代码工作方式，我只是希望它简短。

这是我的代码

 private void button1_Click(object sender, EventArgs e)
    {
        Microsoft.Office.Interop.Excel.Application OfficeExcel;
        Microsoft.Office.Interop.Excel._Workbook OfficeWorkBook;
        Microsoft.Office.Interop.Excel._Worksheet OfficeSheet;
        var dtpMonth = dateTimePicker1.Value.ToString("MMMM");
        var dtpYear = dateTimePicker1.Value.Year;
        var MonthYear = dtpMonth + " - " + dtpYear;
        var dtpDay = dateTimePicker1.Value.Day;
        try
        {
            OfficeExcel = new Microsoft.Office.Interop.Excel.Application();
            OfficeExcel.Visible = true;
            int appletotal = Convert.ToInt32(lblappletotal.Text);
            int bananatotal = Convert.ToInt32(lblbananatotal.Text);
            int orangetotal = Convert.ToInt32(lblorangetotal.Text);
            int grapestotal = Convert.ToInt32(lblgrapestotal.Text);
            switch (dateTimePicker1.Value.Day.ToString())
            { 
                case "1":
                     OfficeWorkBook = (Microsoft.Office.Interop.Excel._Workbook)(OfficeExcel.Workbooks.Add(""));
                     OfficeSheet = (Microsoft.Office.Interop.Excel._Worksheet)OfficeWorkBook.ActiveSheet;
                    OfficeSheet.Cells[3,1] = "apple";
                    OfficeSheet.Cells[4,1] = "banana";
                    OfficeSheet.Cells[5,1] = "orange";
                    OfficeSheet.Cells[6,1] = "grapes";
                    OfficeSheet.Cells[2, 2] = dtpDay + dtpMonth ;
                    OfficeSheet.Cells[3, 2] = appletotal; // variable
                    OfficeSheet.Cells[4, 2] = bananatotal;
                    OfficeSheet.Cells[5, 2] = orangetotal;
                    OfficeSheet.Cells[6, 2] = grapestotal;
                    OfficeExcel.Visible = true;

                    OfficeWorkBook.SaveAs("D:''fruits''" + MonthYear + ".xls", Microsoft.Office.Interop.Excel.XlFileFormat.xlExcel7, Type.Missing, Type.Missing,
                                    false, false, Microsoft.Office.Interop.Excel.XlSaveAsAccessMode.xlNoChange,
                                    Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing);

                     break;

                case "2":
                    OfficeWorkBook = OfficeExcel.Workbooks.Open("D:''fruits''" + MonthYear + ".xls");
                    OfficeSheet = (Excel.Worksheet)OfficeWorkBook.Worksheets.get_Item(1);
                    OfficeSheet.Cells[2, 3] = dtpDay + dtpMonth;
                    OfficeSheet.Cells[3, 3] = appletotal;
                    OfficeSheet.Cells[4, 3] = bananatotal;
                    OfficeSheet.Cells[5, 3] = orangetotal;
                    OfficeSheet.Cells[6, 3] = grapestotal;
                    OfficeExcel.Visible = true;
                    OfficeWorkBook.Save();
                    break;
                    .
                    .
                    .
                    so On.....
    }

感谢

int DayCell = dateTimePicker1.Value.Day+1;
OfficeSheet.Cells[2, Daycell] = dtpDay + dtpMonth ;