Enigmatry.Entry.Csv 9.1.1-preview.4

CSV Processing Library

A library that provides functionality for reading and writing CSV files, with support for complex mapping, validation, and transformation.

Intended Usage

Use this library when you need to import or export data in CSV format, with strong typing and customizable mapping between your domain models and CSV records.

Installation

Add the package to your project:

dotnet add package Enigmatry.Entry.Csv

Usage Examples

Reading a CSV file:

using System;
using System.IO;
using System.Collections.Generic;
using Enigmatry.Entry.Csv;

// Define your model
public class Person
{
    public string FirstName { get; set; } = string.Empty;
    
    [Name("Last Name")]
    public string LastName { get; set; } = string.Empty;
    
    [Name("Date of Birth")]
    public DateTime BirthDate { get; set; }
    
    [Name("Email Address")]
    public string Email { get; set; } = string.Empty;
    
    [Ignore]
    public string InternalId { get; set; } = string.Empty;
}

// Read CSV file
public List<Person> ReadPeopleFromCsv(string filePath)
{
    // Create CSV helper with options
    var csvHelper = new CsvHelper<Person>(options => 
    {
        options.WithCulture(System.Globalization.CultureInfo.InvariantCulture);
    });
    
    using var fileStream = File.OpenRead(filePath);
    var people = csvHelper.GetRecords(fileStream).ToList();
    
    return people;
}

Writing a CSV file:

using System;
using System.IO;
using System.Collections.Generic;
using System.Text;
using Enigmatry.Entry.Csv;

// Create some data
var people = new List<Person>
{
    new Person 
    { 
        FirstName = "John", 
        LastName = "Doe", 
        BirthDate = new DateTime(1980, 1, 1), 
        Email = "john@example.com",
        InternalId = "JD001" // This will be ignored in the CSV output because of the [Ignore] attribute
    },
    new Person 
    { 
        FirstName = "Jane", 
        LastName = "Smith", 
        BirthDate = new DateTime(1985, 5, 5), 
        Email = "jane@example.com",
        InternalId = "JS002" 
    }
};

// Write to CSV file
public void ExportPeopleToCsv(List<Person> people, string outputFilePath)
{
    var csvHelper = new CsvHelper<Person>(options => 
    {
        options.WithEncoding(Encoding.UTF8);
        options.WithCulture(System.Globalization.CultureInfo.InvariantCulture);
    });
    
    // Generate CSV data
    byte[] csvData = csvHelper.WriteRecords(people);
    
    // Save to file
    File.WriteAllBytes(outputFilePath, csvData);
}

Additional Examples

Working with DateTimeOffset values:

using System;
using System.Collections.Generic;
using Enigmatry.Entry.Csv;

public class Event
{
    public string Name { get; set; } = string.Empty;
    
    [Name("Event Time")]
    public DateTimeOffset EventTime { get; set; }
}

public void ProcessEventsCsv(string filePath)
{
    // The built-in DateTimeOffsetToLocalDateTimeConverter will automatically handle converting 
    // DateTimeOffset values to local date-time strings when writing CSV data
    var csvHelper = new CsvHelper<Event>(options => 
    {
        options.WithCulture(System.Globalization.CultureInfo.InvariantCulture);
    });
    
    // Example writing events with DateTimeOffset
    var events = new List<Event>
    {
        new Event { Name = "Conference", EventTime = DateTimeOffset.Now },
        new Event { Name = "Workshop", EventTime = DateTimeOffset.Now.AddDays(1) }
    };
    
    byte[] csvData = csvHelper.WriteRecords(events);
    
    // CSV will show local dates in "yyyy-MM-dd HH:mm:ss" format
}