How to Parse CSV File in C#

1. Parse CSV File With the TextFieldParser Class in C#
2. Parse CSV File With the FileHelpers Library in C#

This tutorial will discuss the methods to parse a CSV file in C#.

Parse CSV File With the TextFieldParser Class in C#

To use the TextFieldParser class, we have to reference the Microsoft.VisualBasic.dll in our C# code. The TextFieldParser class contains many methods for parsing structured text files in C#. We can read a CSV file with the TextFieldParser class by setting the delimiters to , with the SetDelimiters() function inside the TextFieldParser class. The following code example shows us how to parse a CSV file with the TextFieldParser class in C#.

using System;
using Microsoft.VisualBasic.FileIO;

namespace parse_csv {
  class Program {
    static void Main(string[] args) {
      using (TextFieldParser textFieldParser = new TextFieldParser(@"C:\File\Sheet1.csv")) {
        textFieldParser.TextFieldType = FieldType.Delimited;
        textFieldParser.SetDelimiters(",");
        while (!textFieldParser.EndOfData) {
          string[] rows = textFieldParser.ReadFields();
        }
      }
    }
  }
}

In the above code, we initialized the instance textFieldParser of the TextFieldParser class by specifying the path to our CSV file in the constructor. We then set our text field type to be delimited with the textFieldParser.TextFieldType = FieldType.Delimited and set , as the delimiter with textFieldParser.SetDelimiter(',') function. We then used a while loop to read the CSV file to the end with the textFieldParser.EndofData. We stored the data inside an array of strings with the ReadFields() function.

Parse CSV File With the FileHelpers Library in C#

The FileHelpers library is used to read and write data to files, streams, and strings in C#. It is a third-party library and does not come pre-installed with the .NET framework. We can easily install it by searching it in the NuGet package manager in the Visual Studio IDE. We can use the FileHelpersEngine class to parse data from a CSV file in C#. The FileHelperEngine class gets the data from the file into class objects in C#. So, we have first to create a model class that can hold our data from the file. The class would contain fields that represent columns in the CSV file. We can use the [DelimitedRecord(",")] to specify that the , is used as a delimiter here. We can use the ReadFile(path) function to read data inside an array of class objects from the file in the specified path. The following code example shows us how to parse a CSV file with the FileHelpers library in C#.

using FileHelpers;
using System;
namespace parse_csv {
  [DelimitedRecord(",")]
  public class Record {
    public string Name;

    public string Age;
  }
  class Program {
    static void Main(string[] args) {
      var fileHelperEngine = new FileHelperEngine<Record>();
      var records = fileHelperEngine.ReadFile(@"C:\File\records.csv");

      foreach (var record in records) {
        Console.WriteLine(record.Name);
        Console.WriteLine(record.Age);
      }
    }
  }
}

Output:

Name
Age
MMA
22
SDA
19
SHA
11

In the above code, we read the data inside the C:\File\records.csv file and save it in an array of objects of the Record class with the FileHelpers library in C#.