SimpleObjects2CSV 2.0.0

SimpleObjects2CSV

A tiny object-to-CSV exporter for simple .NET admin tools, tests, support dumps, and quick internal exports.

Convert a collection of plain objects into CSV using public properties as columns. No mapping profiles, no CSV reading, no heavy dependencies.

Install

dotnet add package SimpleObjects2CSV

Getting a CSV string

using SimpleObjects2CSV;

var people = new List<Person>
{
    new() { Name = "Alice", Age = 30 },
    new() { Name = "Bob", Age = 25 },
};

string csv = CSV.GetCSVString(people);
// Age,Name
// 30,Alice
// 25,Bob

IEnumerable<T> is supported:

string csv = CSV.GetCSVString(people.AsEnumerable());

List<string> exports each item as a single Value column:

string csv = CSV.GetCSVString(new List<string> { "alpha", "beta" });
// Value
// alpha
// beta

Writing a CSV file

// filename + directory (legacy API)
CSV.ExportCSV(people, "people.csv", @"C:\Exports");

// full file path
CSV.ExportCSV(people, @"C:\Exports\people.csv");

// write an existing CSV string
CSV.ExportCSV(csv, "people.csv", @"C:\Exports");

Directories are created automatically. Files are written as UTF-8 without BOM.

Skipping properties with [CsvIgnore]

public class User
{
    public string Name { get; set; }

    [CsvIgnore]
    public string Password { get; set; }
}

Custom column headers with [CsvName]

public class User
{
    [CsvName("Display Name")]
    public string FullName { get; set; }
}

Headers containing commas or quotes are escaped automatically.

Async export

await CSV.ExportCSVAsync(people, @"C:\Exports\people.csv");

await CSV.ExportCSVAsync(people, "people.csv", @"C:\Exports", cancellationToken: cancellationToken);

Formatting notes

• Columns are ordered alphabetically by property name (not declaration order).
• Column headers and values are CSV-escaped when they contain commas, quotes, or newlines.
• List<string> / IEnumerable<string> exports each string as a single Value column.
• Types with no exportable properties throw InvalidOperationException.
• Duplicate [CsvName] headers on the same type throw InvalidOperationException.
• Properties hidden with new on a derived type use the derived declaration.
• Null property values export as empty fields.
• Null items in the source collection are skipped (no row is written for them).
• Numbers, decimals, floats, and doubles use invariant culture by default. Floats and doubles use round-trip (R) format.
• DateTime, DateTimeOffset, DateOnly, and TimeOnly always use invariant ISO 8601 (O) format, regardless of IFormatProvider.
• Booleans use invariant True/False text; IFormatProvider does not change them.
• Pass an IFormatProvider to format numeric values with a specific culture:

string csv = CSV.GetCSVString(people, new CultureInfo("de-DE"));
CSV.ExportCSV(people, "people.csv", @"C:\Exports", new CultureInfo("de-DE"));

• Async methods honour CancellationToken during file writes. On netstandard2.0, cancellation is checked between write chunks.

Security note

CSV files opened in spreadsheet applications may execute formulas when a cell value begins with =, +, -, @, or a tab character. Sanitise or prefix untrusted values if exports may be opened in Excel or similar tools.

License

Apache-2.0