ExcelCell Formula

GemBox.Spreadsheet can read and write formulas, but the level of support depends on the Excel file format:

  • In XLS, all common and some advanced formulas are supported.
  • In XLSX, all formulas are supported. You only need to avoid array formulas in template files.
  • In ODS, all formulas are supported. However, OpenOffice formulas don't have the same syntax as Excel formulas.

Formulas can't be exported to CSV, HTML, PDF or XPS file formats.

Also note that formula values are automatically calculated when a file is opened in Excel.

Screenshot
ExcelCell Formula Screenshot

See the full code below, use Run Example to execute. 

using GemBox.Spreadsheet;
using System;
using System.IO;

class Sample
{
    [STAThread]
    static void Main(string[] args)
    {
        // If using Professional version, put your serial key below.
        SpreadsheetInfo.SetLicense("FREE-LIMITED-KEY");

        ExcelFile ef = new ExcelFile();
        ExcelWorksheet ws = ef.Worksheets.Add("Formula");

        int rowIndex = 0;

        ws.Columns[0].Width = 35 * 256;
        ws.Columns[1].Width = 15 * 256;
        ws.Columns[2].Width = 15 * 256;

        ws.Cells[rowIndex++, 0].Value = "Examples of typical formulas usage:";

        ws.Cells[++rowIndex, 0].Value = "Some data:";
        ws.Cells[rowIndex, 1].SetValue(3);
        ws.Cells[rowIndex, 2].SetValue(4.1);
        ws.Cells[++rowIndex, 1].SetValue(5.2);
        ws.Cells[rowIndex, 2].SetValue(6);
        ws.Cells[++rowIndex, 1].SetValue(7);
        ws.Cells[rowIndex++, 2].SetValue(8.3);

        // Named ranges.
        string namedRange = "Range1";
        ws.NamedRanges.Add(namedRange, ws.Cells.GetSubrange("B3", "C4"));

        // Floats without first digit.
        ws.Cells[++rowIndex, 0].Value = "Float number without first digit:";
        ws.Cells[rowIndex, 1].Formula = "=.5/23+.1-2";

        // Function using named range.
        ws.Cells[++rowIndex, 0].Value = "Named range:";
        ws.Cells[rowIndex, 1].Formula = "=SUM(" + namedRange + ")";

        // Function's miss argument.
        ws.Cells[++rowIndex, 0].Value = "Function's miss arguments:";
        ws.Cells[rowIndex, 1].Formula = "=Count(1,  ,  ,,,2, 23,,,,,, 34,,,54,,,,  ,)";

        // Functions are case-insensitive.
        ws.Cells[++rowIndex, 0].Value = "Functions are case-insensitive:";
        ws.Cells[rowIndex, 1].Formula = "=cOs( 1 )";

        // Functions.
        ws.Cells[++rowIndex, 0].Value = "Supported functions:";

        string nextFunction;
        ws.Cells[++rowIndex, 0].Value = "Results";
        ws.Cells[rowIndex++, 1].Value = "Formulas";

        nextFunction = "=NOW()+123";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        nextFunction = "=SECOND(12)/23";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        nextFunction = "=MINUTE(24)-1343/35";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        nextFunction = "=(HOUR(56)-23/35)";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        nextFunction = "=WEEKDAY(5)";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        nextFunction = "=YEAR(23)-WEEKDAY(5)";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        nextFunction = "=MONTH(3)-2342/235345";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        nextFunction = "=((DAY(1)))";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        nextFunction = "=TIME(1,2,3)";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        nextFunction = "=DATE(1,2,3)";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        nextFunction = "=RAND()";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        nextFunction = "=TEXT(\"text\", \"$d\")";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        nextFunction = "=VAR(1,2)";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        nextFunction = "=MOD(1,2)";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        nextFunction = "=NOT(FALSE)";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        nextFunction = "=OR(FALSE)";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        nextFunction = "=AND(TRUE)";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        nextFunction = "=FALSE()";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        nextFunction = "=TRUE()";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        nextFunction = "=VALUE(3)";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        nextFunction = "=LEN(\"hello\")";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        nextFunction = "=MID(\"hello\",1,1)";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        nextFunction = "=ROUND(1,2)";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        nextFunction = "=SIGN(-2)";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        nextFunction = "=INT(3)";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        nextFunction = "=ABS(-3)";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        nextFunction = "=LN(2)";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        nextFunction = "=EXP(4)";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        nextFunction = "=SQRT(2)";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        nextFunction = "=PI()";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        nextFunction = "=COS(4)";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        nextFunction = "=SIN(3)";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        nextFunction = "=MAX(1,2)";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        nextFunction = "=MIN(1,2)";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        nextFunction = "=AVERAGE(1,2)";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        nextFunction = "=SUM(1,3)";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        nextFunction = "=IF(1,2,3)";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        nextFunction = "=COUNT(1,2,3)";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        nextFunction = "=SUBTOTAL(1,B3:C5)";
        ws.Cells[rowIndex, 0].Formula = nextFunction;
        ws.Cells[rowIndex++, 1].Value = nextFunction;

        // Paranthless checks.
        ws.Cells[++rowIndex, 0].Value = "Paranthless:";
        ws.Cells[rowIndex, 1].Formula = "=((12+2343+34545))";

        // Unary operators.
        ws.Cells[++rowIndex, 0].Value = "Unary operators:";
        ws.Cells[rowIndex, 1].Formula = "=B5%";
        ws.Cells[rowIndex, 2].Formula = "=+++B5";

        // Operand tokens, bool.
        ws.Cells[++rowIndex, 0].Value = "Bool values:";
        ws.Cells[rowIndex, 1].Formula = "=TRUE";
        ws.Cells[rowIndex, 2].Formula = "=FALSE";

        // Operand tokens, int.
        ws.Cells[++rowIndex, 0].Value = "Integer values:";
        ws.Cells[rowIndex, 1].Formula = "=1";
        ws.Cells[rowIndex, 2].Formula = "=20";

        // Operand tokens, num.
        ws.Cells[++rowIndex, 0].Value = "Float values:";
        ws.Cells[rowIndex, 1].Formula = "=.4";
        ws.Cells[rowIndex, 2].Formula = "=2235.5132";

        // Operand tokens, str.
        ws.Cells[++rowIndex, 0].Value = "String values:";
        ws.Cells[rowIndex, 1].Formula = "=\"hello world!\"";

        // Operand tokens, error.
        ws.Cells[++rowIndex, 0].Value = "Error values:";
        ws.Cells[rowIndex, 1].Formula = "=#NULL!";
        ws.Cells[rowIndex, 2].Formula = "=#DIV/0!";

        // Binary operators.
        ws.Cells[++rowIndex, 0].Value = "Binary operators:";
        ws.Cells[rowIndex, 1].Formula = "=(1)-(2)+(3/2+34)/2+12232-32-4";

        ef.Save("Formula.xlsx");
    }
}
Imports GemBox.Spreadsheet
Imports System.IO

Module Samples

    Sub Main()

        ' If using Professional version, put your serial key below.
        SpreadsheetInfo.SetLicense("FREE-LIMITED-KEY")

        Dim ef As ExcelFile = New ExcelFile
        Dim ws As ExcelWorksheet = ef.Worksheets.Add("Formula")

        Dim rowIndex As Integer = 0

        ws.Columns(0).Width = 35 * 256
        ws.Columns(1).Width = 15 * 256
        ws.Columns(2).Width = 15 * 256

        ws.Cells(rowIndex, 0).Value = "Examples of typical formulas usage:"
        rowIndex = rowIndex + 2

        ws.Cells(rowIndex, 0).Value = "Some data:"
        ws.Cells(rowIndex, 1).SetValue(3)
        ws.Cells(rowIndex, 2).SetValue(4.1)
        rowIndex = rowIndex + 1
        ws.Cells(rowIndex, 1).SetValue(5.2)
        ws.Cells(rowIndex, 2).SetValue(6)
        rowIndex = rowIndex + 1
        ws.Cells(rowIndex, 1).SetValue(7)
        ws.Cells(rowIndex, 2).SetValue(8.3)
        rowIndex = rowIndex + 1

        ' Named ranges.
        Dim namedRange As String = "Range1"
        ws.NamedRanges.Add(namedRange, ws.Cells.GetSubrange("B3", "C4"))

        ' Floats without first digit.
        rowIndex = rowIndex + 1
        ws.Cells(rowIndex, 0).Value = "Float number without first digit:"
        ws.Cells(rowIndex, 1).Formula = "=.5/23+.1-2"

        ' Function using named range.
        rowIndex = rowIndex + 1
        ws.Cells(rowIndex, 0).Value = "Named range:"
        ws.Cells(rowIndex, 1).Formula = "=SUM(" + namedRange + ")"

        ' Function's miss argument.
        rowIndex = rowIndex + 1
        ws.Cells(rowIndex, 0).Value = "Function's miss arguments:"
        ws.Cells(rowIndex, 1).Formula = "=Count(1,  ,  ,,,2, 23,,,,,, 34,,,54,,,,  ,)"

        ' Functions are case-insensitive.
        rowIndex = rowIndex + 1
        ws.Cells(rowIndex, 0).Value = "Functions are case-insensitive:"
        ws.Cells(rowIndex, 1).Formula = "=cOs( 1 )"

        ' Functions.
        rowIndex = rowIndex + 1
        ws.Cells(rowIndex, 0).Value = "Supported functions:"

        Dim nextFunction As String
        rowIndex = rowIndex + 1
        ws.Cells(rowIndex, 0).Value = "Results"
        ws.Cells(rowIndex, 1).Value = "Formulas"
        rowIndex = rowIndex + 1

        nextFunction = "=NOW()+123"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        nextFunction = "=SECOND(12)/23"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        nextFunction = "=MINUTE(24)-1343/35"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        nextFunction = "=(HOUR(56)-23/35)"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        nextFunction = "=WEEKDAY(5)"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        nextFunction = "=YEAR(23)-WEEKDAY(5)"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        nextFunction = "=MONTH(3)-2342/235345"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        nextFunction = "=((DAY(1)))"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        nextFunction = "=TIME(1,2,3)"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        nextFunction = "=DATE(1,2,3)"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        nextFunction = "=RAND()"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        nextFunction = "=TEXT(" + Chr(34) + "text" + Chr(34) + ", " + Chr(34) + "$d" + Chr(34) + ")"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        nextFunction = "=VAR(1,2)"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        nextFunction = "=MOD(1,2)"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        nextFunction = "=NOT(FALSE)"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        nextFunction = "=OR(FALSE)"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        nextFunction = "=AND(TRUE)"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        nextFunction = "=FALSE()"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        nextFunction = "=TRUE()"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        nextFunction = "=VALUE(3)"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        nextFunction = "=LEN(" + Chr(34) + "hello" + Chr(34) + ")"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        nextFunction = "=MID(" + Chr(34) + "hello" + Chr(34) + ",1,1)"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        nextFunction = "=ROUND(1,2)"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        nextFunction = "=SIGN(-2)"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        nextFunction = "=INT(3)"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        nextFunction = "=ABS(-3)"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        nextFunction = "=LN(2)"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        nextFunction = "=EXP(4)"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        nextFunction = "=SQRT(2)"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        nextFunction = "=PI()"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        nextFunction = "=COS(4)"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        nextFunction = "=SIN(3)"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        nextFunction = "=MAX(1,2)"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        nextFunction = "=MIN(1,2)"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        nextFunction = "=AVERAGE(1,2)"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        nextFunction = "=SUM(1,3)"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        nextFunction = "=IF(1,2,3)"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        nextFunction = "=COUNT(1,2,3)"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        nextFunction = "=SUBTOTAL(1,B3:C5)"
        ws.Cells(rowIndex, 0).Formula = nextFunction
        ws.Cells(rowIndex, 1).Value = nextFunction
        rowIndex = rowIndex + 1

        ' Paranthless checks.
        rowIndex = rowIndex + 1
        ws.Cells(rowIndex, 0).Value = "Paranthless:"
        ws.Cells(rowIndex, 1).Formula = "=((12+2343+34545))"

        ' Unary operators.
        rowIndex = rowIndex + 1
        ws.Cells(rowIndex, 0).Value = "Unary operators:"
        ws.Cells(rowIndex, 1).Formula = "=B5%"
        ws.Cells(rowIndex, 2).Formula = "=+++B5"

        ' Operand tokens, bool.
        rowIndex = rowIndex + 1
        ws.Cells(rowIndex, 0).Value = "Bool values:"
        ws.Cells(rowIndex, 1).Formula = "=TRUE"
        ws.Cells(rowIndex, 2).Formula = "=FALSE"

        ' Operand tokens, int.
        rowIndex = rowIndex + 1
        ws.Cells(rowIndex, 0).Value = "Integer values:"
        ws.Cells(rowIndex, 1).Formula = "=1"
        ws.Cells(rowIndex, 2).Formula = "=20"

        ' Operand tokens, num.
        rowIndex = rowIndex + 1
        ws.Cells(rowIndex, 0).Value = "Float values:"
        ws.Cells(rowIndex, 1).Formula = "=.4"
        ws.Cells(rowIndex, 2).Formula = "=2235.5132"

        ' Operand tokens, str.
        rowIndex = rowIndex + 1
        ws.Cells(rowIndex, 0).Value = "String values:"
        ws.Cells(rowIndex, 1).Formula = "=" + Chr(34) + "hello world!" + Chr(34)

        ' Operand tokens, error.
        rowIndex = rowIndex + 1
        ws.Cells(rowIndex, 0).Value = "Error values:"
        ws.Cells(rowIndex, 1).Formula = "=#NULL!"
        ws.Cells(rowIndex, 2).Formula = "=#DIV/0!"

        ' Binary operators.
        rowIndex = rowIndex + 1
        ws.Cells(rowIndex, 0).Value = "Binary operators:"
        ws.Cells(rowIndex, 1).Formula = "=(1)-(2)+(3/2+34)/2+12232-32-4"

        ef.Save("Formula.xlsx")

    End Sub

End Module