A structured expense register

How it works

1. Preserve data types

   Write DateTime and numeric values directly. Apply date and decimal formats for a readable display.

2. Add entry guidance

   Declare validation lists for category and status, then wrap the populated area in an Excel table.

3. Calculate the total

   Use SUM over the amount cells, evaluate the workbook, and render the register. The four sample expenses total 385.15 EUR.

This is the complete example file used to generate the download. The walkthrough runner creates the output directory and produces the additional previews.

using System;
using System.IO;
using OfficeIMO.Drawing;
using OfficeIMO.Excel;

namespace OfficeIMO.Examples.Showcase.Workflows;

/// <summary>Builds an expense register with real date cells, currency formats, and list validation.</summary>
internal static class ExpenseRegister {
    internal static void Create(string folder) {
        using ExcelDocument document = ExcelDocument.Create(Path.Combine(folder, "example.xlsx"));
        ExcelSheet sheet = document.AddWorksheet("Expenses");
        sheet.MergeRange("A1:E1");
        sheet.Cell(1, 1, "September expense register");
        sheet.CellFontSize(1, 1, 20);
        sheet.CellBold(1, 1, true);
        sheet.CellFontColor(1, 1, "17365D");
        string[] headers = { "Date", "Description", "Category", "Amount (EUR)", "Status" };
        for (int column = 0; column < headers.Length; column++) {
            sheet.Cell(4, column + 1, headers[column]);
            sheet.SetColumnWidth(column + 1, column == 1 ? 32 : 21);
        }
        var expenses = new[] {
            (Day: 2, Description: "Client workshop travel", Category: "Travel", Amount: 184.50),
            (Day: 4, Description: "Training materials", Category: "Training", Amount: 62.00),
            (Day: 7, Description: "Project meeting", Category: "Meals", Amount: 48.75),
            (Day: 9, Description: "Replacement headset", Category: "Equipment", Amount: 89.90)
        };
        for (int index = 0; index < expenses.Length; index++) {
            int row = index + 5;
            var expense = expenses[index];
            sheet.Cell(row, 1, new DateTime(2026, 9, expense.Day), numberFormat: "dd mmm yyyy");
            sheet.Cell(row, 2, expense.Description);
            sheet.Cell(row, 3, expense.Category);
            sheet.Cell(row, 4, expense.Amount, numberFormat: "#,##0.00");
            sheet.Cell(row, 5, index < 2 ? "Approved" : "Submitted");
        }
        sheet.AddTable("A4:E8", true, "Expenses", ExcelTableStyle.TableStyleMedium2);
        sheet.ValidationList("C5:C8", new[] { "Travel", "Training", "Meals", "Equipment" });
        sheet.ValidationList("E5:E8", new[] { "Submitted", "Approved", "Returned" });
        sheet.Cell(10, 3, "Total");
        sheet.CellFormula(10, 4, "SUM(D5:D8)");
        sheet.FormatCell(10, 4, "#,##0.00");
        sheet.CellBold(10, 4, true);
        sheet.Freeze(topRows: 4);
        document.Calculate();
        sheet.Range("A1:E12").ExportImage(OfficeImageExportFormat.Png)
            .Save(Path.Combine(folder, "preview.png"), OfficeImageExportFileConflictPolicy.Replace);
        document.Save();
    }
}

Run it from the source checkout

Clone the OfficeIMO repository and run this command from its root with the .NET 10 SDK. The first run restores the example project's dependencies.

dotnet run --project OfficeIMO.Examples -f net10.0 -- --showcase-workflows --showcase-example excel-expense-register

The files are written to OfficeIMO.Examples/bin/Debug/net10.0/Documents/Workflows/excel-expense-register/. To use the example in your application, start with the Excel guide and its package setup.

Continue with another example

• ExcelValidated spreadsheet inputs
• ExcelExport application records to Excel
• ExcelPricing with named ranges