ExcelApplication supports all math, string, boolean, time, statistical, database, lookup and reference formulas or functions that are part of Excel. ExcelWriter does not calculate formulas at run-time; all formulas are calculated when the workbook is opened in Excel.

To insert a formula in a cell, use the propertyCell.Formula. Begin the formula string with =, as you would when entering a formula in Microsoft Excel:

sheet1.Cells["A25"].Formula = "=SUM(A4:A24)";

ExcelWriter allows you to use values from a different sheet when assigning a formula to a cell, as in the following examples:

sheet1.Cells[5,3].Formula = "=SUM(Sheet1!A1:A3,Sheet3!A1:A5)";

The property Cell.Name returns a cell's Excel-style name (e.g., "B5"). This property can be useful if you want to build a formula string using row and column indexes, rather than cell names, for example:

String formula = "=SUM(" + sheet1.Cells[3, 1].Name +
     ":" + sheet1.Cells[23, 1].Name + ")";
sheet1.Cells[24, 1].Formula = formula;

Example

Here is an example ASP.NET Page class that demonstrates how to use Formulas with ExcelApplication:

using SoftArtisans.OfficeWriter.ExcelWriter;

public class FormulaDemo : System.Web.UI.Page
{
     protected void Page_Load(object sender, System.EventArgs e)
     {
          //--- Create ExcelApplication, a Workbook, and a Worksheet
          ExcelApplication xlw = new ExcelApplication();
          Workbook wb = xlw.Create();
          Worksheet sheet1 = wb.Worksheets[0];

          //--- Write some values into cells for the
          //--- formulas to compute
          sheet1.Cells["A1"].Value = 1;
          sheet1.Cells["A2"].Value = 2;
          sheet1.Cells["A3"].Value = 3;

          //--- Write a formula into a cell
          //--- Formula will be calculated
          //--- when opened in Excel
          sheet1.Cells["A4"].Formula = "=SUM(A1:A3)";

          //--- Save the workbook
          xlw.Save(wb, Page.Response, "Generated.xls", false);
     }
}

Code Sample: ExcelApplication Basic Steps

This sample shows many of the core features of ExcelApplication, including the use of formulas.

[C#] | [VB.NET]