Sheleski.DelimitedFile

Library for parsing and saving CSV and Tab Delimited Files in .NET.

Usage

The CsvFile has a very simple API with Headers and Values properties. Use these properties to work with the data in the CSV file.

CsvFile csv = new CsvFile();

csv.Headers = new string[]{ "First Name", "Last Name" };
csv.Values = new string[][]
{
  new string[]{"Joe", "Blow"},
  new string[]{"Bonehead", "McGee"}
};

Save the CSV to file

csv.Save("c:\\temp\\names.csv");

Write the CSV to any arbitrary TextReader

using (var writer = new StringWriter())
{
    csv.Write(writer);

    string csvString = writer.ToString();
}

Load a CSV from a stream

WebRequest request = HttpWebRequest.Create("https://raw.githubusercontent.com/forxer/languages-list/master/src/Languages.csv");
using (WebResponse response = await request.GetResponseAsync())
using (var stream = response.GetResponseStream())
using (var reader = new StreamReader(stream))
{
  var csvFile = CsvFile.Load(reader, CsvFileLoadOptions.WithHeaders);
}

Create a Delimited File from any IEnumerable easily.

You can easily generate a CSV file from a collection.

Start with a Person class.

class Person
{
    [Display(Order = 1, Name = "First Name")]
    public string FirstName { get; set; }

    [Display(Order = 2, Name = "Last Name")]
    public string LastName { get; set; }

    [Display(Order = 3, Name = "Birth Date")]
    public DateTime BirthDate { get; set; }

    [Display(Order = 4, Name = "Death Date")]
    public DateTime? DeathDate { get; set; }

    [Display(Order = -1)]
    public string InvisibleInfo { get; set; }

    [Display(Order = 4)]
    public List<Person> Children { get; } = new List<Person>();
}

Now lets create some people and make a CSV File from it.

First make sure to include the using directive.

using Sheleski.DelimitedFile;

Now we can make use of the .ToCsvFile() extension method.

Person[] people = new Person[]
{
    new Person{FirstName = "Elvis", LastName = "Presley", BirthDate = new DateTime(1935, 1, 8), DeathDate= null, InvisibleInfo = "Dead??"},
    new Person{FirstName = "Abraham", LastName = "Lincoln", BirthDate = new DateTime(1809, 2, 12), DeathDate = new DateTime(1865, 4, 15), InvisibleInfo = "Dead"},
};

CsvFile csvFile = people.ToCsvFile();

Resulting CSV string:

First Name,Last Name,Birth Date,Death Date,Children
Elvis,Presley,1/8/1935 12:00:00 AM,,System.Collections.Generic.List`1[Sheleski.DelimitedFile.Tests.CsvFile_EnumerableExtensions+Person]
Abraham,Lincoln,2/12/1809 12:00:00 AM,4/15/1865 12:00:00 AM,System.Collections.Generic.List`1[Sheleski.DelimitedFile.Tests.CsvFile_EnumerableExtensions+Person]

Automatic Column Mapping

If you do not pass a mapping to the .ToCSVFile() extension method, then it will generate an automatic mapping by looking at the DisplayAttributes assigned to the properties.

The Order property of the DisplayAttribute determines the order of the columns generated in the resulting Delimited File.

Note: If you do not want a column to be added to the resulting delimited file, the Order property can be set to a negative value.

The Name property of the DisplayAttribute determines the column header generated for the associated property.

The values used to populate the delimted file are generated by simply calling the ToString() method of each property.

Custom Column Mapping

DelimitedFileObjectMapping<Person> mapping = new DelimitedFileObjectMapping<Person>();
mapping.AddProperty(x => x.BirthDate).WithValue(d => d.ToShortDateString()).WithHeader("B-Day");
mapping.AddProperty(x => x.LastName);
mapping.AddProperty(x => x.FirstName).WithHeader("F Name");
mapping.AddProperty(x => x.DeathDate);

mapping.Add("Row Index", (x, i) => i.ToString());


CsvFile csvFile = people.ToCsvFile(mapping);

The example above shows how to add mappings to generate a CSV file by adding the Properties. You can also add computed values as well (See the Row Index example above).