Create and write Excel files in C# and VB.NET

using GemBox.Spreadsheet;

class Program
{
    static void Main()
    {
        // If using the Professional version, put your serial key below.
        SpreadsheetInfo.SetLicense("FREE-LIMITED-KEY");

        // Create new empty workbook.
        var workbook = new ExcelFile();

        // Add new sheet.
        var worksheet = workbook.Worksheets.Add("Skyscrapers");

        // Write title to Excel cell.
        worksheet.Cells["A1"].Value = "List of tallest buildings (2021):";

        // Tabular sample data for writing into an Excel file.
        var skyscrapers = new object[,]
        {
             { "Rank", "Building", "City", "Country", "Metric", "Imperial", "Floors", "Built (Year)" },
             { 1, "Burj Khalifa", "Dubai", "United Arab Emirates", 828, 2717, 163, 2010 },
             { 2, "Shanghai Tower", "Shanghai", "China", 632, 2073, 128, 2015 },
             { 3, "Abraj Al-Bait Clock Tower", "Mecca", "Saudi Arabia", 601, 1971, 120, 2012 },
             { 4, "Ping An Finance Centre", "Shenzhen", "China", 599, 1965, 115, 2017 },
             { 5, "Lotte World Tower", "Seoul", "South Korea", 554.5, 1819, 123, 2016 },
             { 6, "One World Trade Center", "New York City", "United States", 541.3, 1776, 104, 2014 },
             { 7, "Guangzhou CTF Finance Centre", "Guangzhou", "China", 530, 1739, 111, 2016 },
             { 7, "Tianjin CTF Finance Centre", "Tianjin", "China", 530, 1739, 98, 2019 },
             { 9, "China Zun", "Beijing", "China", 528, 1732, 108, 2018 },
             { 10, "Taipei 101", "Taipei", "Taiwan", 508, 1667, 101, 2004 },
             { 11, "Shanghai World Financial Center", "Shanghai", "China", 492, 1614, 101, 2008 },
             { 12, "International Commerce Centre", "Hong Kong", "China", 484, 1588, 118, 2010 },
             { 13, "Central Park Tower", "New York City", "United States", 472, 1550, 98, 2020 },
             { 14, "Lakhta Center", "St. Petersburg", "Russia", 462, 1516, 86, 2019 },
             { 15, "Landmark 81", "Ho Chi Minh City", "Vietnam", 461.2, 1513, 81, 2018 },
             { 16, "Changsha IFS Tower T1", "Changsha", "China", 452.1, 1483, 88, 2018 },
             { 17, "Petronas Tower 1", "Kuala Lumpur", "Malaysia", 451.9, 1483, 88, 1998 },
             { 17, "Petronas Tower 2", "Kuala Lumpur", "Malaysia", 451.9, 1483, 88, 1998 },
             { 19, "Zifeng Tower", "Nanjing", "China", 450, 1476, 89, 2010 },
             { 19, "Suzhou IFS", "Suzhou", "China", 450, 1476, 98, 2019 }
        };

        // Set row formatting.
        worksheet.Rows["1"].Style = workbook.Styles[BuiltInCellStyleName.Heading1];

        // Set columns width.
        worksheet.Columns["A"].SetWidth(8, LengthUnit.CharacterWidth);  // Rank
        worksheet.Columns["B"].SetWidth(30, LengthUnit.CharacterWidth); // Building
        worksheet.Columns["C"].SetWidth(16, LengthUnit.CharacterWidth); // City
        worksheet.Columns["D"].SetWidth(20, LengthUnit.CharacterWidth); // Country
        worksheet.Columns["E"].SetWidth(9, LengthUnit.CharacterWidth);  // Metric
        worksheet.Columns["F"].SetWidth(11, LengthUnit.CharacterWidth); // Imperial
        worksheet.Columns["G"].SetWidth(9, LengthUnit.CharacterWidth);  // Floors
        worksheet.Columns["H"].SetWidth(9, LengthUnit.CharacterWidth);  // Built (Year)
        worksheet.Columns["I"].SetWidth(4, LengthUnit.CharacterWidth);  // Top 10
        worksheet.Columns["J"].SetWidth(5, LengthUnit.CharacterWidth);  // Top 20

        // Write header data to Excel cells.
        for (int col = 0; col < skyscrapers.GetLength(1); col++)
            worksheet.Cells[3, col].Value = skyscrapers[0, col];
        worksheet.Cells["E3"].Value = "Height";

        worksheet.Cells.GetSubrange("A3:A4").Merged = true;  // Rank
        worksheet.Cells.GetSubrange("B3:B4").Merged = true;  // Building
        worksheet.Cells.GetSubrange("C3:C4").Merged = true;  // City
        worksheet.Cells.GetSubrange("D3:D4").Merged = true;  // Country
        worksheet.Cells.GetSubrange("E3:F3").Merged = true;  // Height
        worksheet.Cells.GetSubrange("G3:G4").Merged = true;  // Floors
        worksheet.Cells.GetSubrange("H3:H4").Merged = true;  // Built (Year)

        // Set header cells formatting.
        var style = new CellStyle();
        style.HorizontalAlignment = HorizontalAlignmentStyle.Center;
        style.VerticalAlignment = VerticalAlignmentStyle.Center;
        style.FillPattern.SetSolid(SpreadsheetColor.FromArgb(237, 125, 49));
        style.Font.Weight = ExcelFont.BoldWeight;
        style.Font.Color = SpreadsheetColor.FromName(ColorName.White);
        style.WrapText = true;
        style.Borders.SetBorders(MultipleBorders.Right | MultipleBorders.Top, SpreadsheetColor.FromName(ColorName.Black), LineStyle.Thin);
        worksheet.Cells.GetSubrange("A3:H4").Style = style;

        // Write "Top 10" cells.
        style = new CellStyle();
        style.HorizontalAlignment = HorizontalAlignmentStyle.Center;
        style.VerticalAlignment = VerticalAlignmentStyle.Center;
        style.Font.Weight = ExcelFont.BoldWeight;
        var mergedRange = worksheet.Cells.GetSubrange("I5:I14");
        mergedRange.Merged = true;
        mergedRange.Value = "T o p   1 0";
        style.Rotation = -90;
        style.FillPattern.SetSolid(SpreadsheetColor.FromArgb(198, 239, 206));
        mergedRange.Style = style;

        // Write "Top 20" cells.
        mergedRange = worksheet.Cells.GetSubrange("J5:J24");
        mergedRange.Merged = true;
        mergedRange.Value = "T o p   2 0";
        style.IsTextVertical = true;
        style.FillPattern.SetSolid(SpreadsheetColor.FromArgb(255, 235, 156));
        mergedRange.Style = style;
        mergedRange = worksheet.Cells.GetSubrange("I15:I24");
        mergedRange.Merged = true;
        mergedRange.Style = style;

        // Write sample data and formatting to Excel cells.
        for (int row = 0; row < skyscrapers.GetLength(0) - 1; row++)
        {
            for (int col = 0; col < skyscrapers.GetLength(1); col++)
            {
                var cell = worksheet.Cells[row + 4, col];
                cell.Value = skyscrapers[row + 1, col];

                cell.Style.Borders[IndividualBorder.Right].LineStyle = LineStyle.Thin;

                if (row % 2 == 0)
                    cell.Style.FillPattern.SetSolid(SpreadsheetColor.FromArgb(221, 235, 247));

                if (col == 0)
                    cell.Style.HorizontalAlignment = HorizontalAlignmentStyle.Center;
                if (col > 3)
                    cell.Style.Font.Name = "Courier New";
                if (col == 4)
                    cell.Style.NumberFormat = "#\" m\"";
                if (col == 5)
                    cell.Style.NumberFormat = "#\" ft\"";
            }
        }

        worksheet.Cells.GetSubrange("A5", "J24").Style.Borders.SetBorders(
            MultipleBorders.Outside, SpreadsheetColor.FromName(ColorName.Black), LineStyle.Medium);
        worksheet.Cells.GetSubrange("A3", "H4").Style.Borders.SetBorders(
            MultipleBorders.Vertical | MultipleBorders.Top, SpreadsheetColor.FromName(ColorName.Black), LineStyle.Medium);
        worksheet.Cells.GetSubrange("A5", "I14").Style.Borders.SetBorders(
            MultipleBorders.Bottom | MultipleBorders.Right, SpreadsheetColor.FromName(ColorName.Black), LineStyle.Medium);

        worksheet.PrintOptions.FitWorksheetWidthToPages = 1;

        // Save workbook as an Excel file.
        workbook.Save("Writing.%OutputFileType%");
    }
}

using GemBox.Spreadsheet;

class Program
{
    static void Main()
    {
        // If using the Professional version, put your serial key below.
        SpreadsheetInfo.SetLicense("FREE-LIMITED-KEY");

        // Create new empty workbook.
        var workbook = new ExcelFile();

        // Add new sheet.
        var worksheet = workbook.Worksheets.Add("Sheet1");

        worksheet.Columns["B"].SetWidth(400, LengthUnit.Pixel);

        // Add plain text to cell.
        worksheet.Cells["B2"].Value = "This is a plain text.";

        // Add rich formatted text to cell.
        worksheet.Cells["B4"].Value = "This is a rich formatted text.";
        worksheet.Cells["B4"].Style.Font.Color = SpreadsheetColor.FromArgb(255, 128, 64);
        worksheet.Cells["B4"].GetCharacters(10, 19).Font.Name = "Arial Black";
        worksheet.Cells["B4"].GetCharacters(15, 9).Font.Size = 14 * 20;
        worksheet.Cells["B4"].GetCharacters(25, 5).Font.Size = 18 * 20;

        // Add HTML formatted text to cell.
        string html = @"<td style='
            font-family: Arial Narrow;
            color: royalblue;
            border: solid black;
            background: #FFF2CC'>This is another rich formatted text.</p>";
        worksheet.Cells["B6"].SetValue(html, LoadOptions.HtmlDefault);

        // Save workbook as an Excel file.
        workbook.Save("Writing.%OutputFileType%");
    }
}