C# Read CSV file in .NET Core using TextFieldParser

Today I am going to talk about a new simple approach to read CSV file in .NET Core using TextFieldParser parser.

In our previous article, we already talked about a couple of approaches like TinyParser and CSVHelper to parse CSV files in .NET Core framework-based applications. CSV files are a popular and useful means of persisting the application data.

Today in this article, we will cover below aspects,

What is TextFieldParser

TextFieldParser class has been ported from the namespace Microsoft.VisualBasic.FileIO, which was originally part of Visual Basic.

Please note that this parser is available for .NET Core 3.0 and above only.

It doesn’t support .NET Core 2.2 and lower versions.

The TextFieldParser provides methods and properties for parsing structured text files and supports parsing for two types of files delimited (CSV) and Fixed width files.

Getting Started

Let’s create a .NET Core application.

To keep it simple I have used the .NET Core C# Console application.

I have used the .NET Core 3.1 version.

Using TextFieldParser for CSV parser

TextFieldParser is a very simple and lightweight parser available for CSV Reading and parsing using C#.

This parser is available by default in .NET Core 3.0 and above. You need to add the below namespace to your file and you are all set to use it.

using Microsoft.VisualBasic.FileIO;

It lets you parse CSV and helps you deserialize the data into proper objects too.

Here is CSV file with data. Let’s use this file as an example and perform a reading.

private static string ReadCSVFile(string csv_file_path)
        {
            DataTable csvData = new DataTable();
            string jsonString = string.Empty;
            try
            {
                using (TextFieldParser csvReader = new TextFieldParser(csv_file_path))
                {
                    csvReader.SetDelimiters(new string[] { "," });
                    csvReader.HasFieldsEnclosedInQuotes = true;
                    string[] colFields;
                    bool tableCreated = false;
                    while (tableCreated == false)
                    {
                        colFields = csvReader.ReadFields();
                        foreach (string column in colFields)
                        {
                            DataColumn datecolumn = new DataColumn(column);
                            datecolumn.AllowDBNull = true;
                            csvData.Columns.Add(datecolumn);
                        }
                        tableCreated = true;
                    }
                    while (!csvReader.EndOfData)
                    {
                        csvData.Rows.Add(csvReader.ReadFields());
                    }
                }
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.Message);
                return "Error:Parsing CSV";
            }
            //if everything goes well, serialize csv to json 
            jsonString = JsonConvert.SerializeObject(csvData);

            return jsonString;
        }

Please see below the client code following namespaces to your code,

Here is the output on the console,

Below is a simple accessor class for UserDetails,

public class UserDetails
    {
        public string ID { get; set; }
        public string Name { get; set; }
        public string City { get; set; }
        public string Country { get; set; }
    }

Other references:

• CSV Parsing in C# using TinyParser and CSVHelper

Do you have any comments or ideas or any better suggestions to share?

Please sound off your comments below.

Happy Coding !!

Summary

TextFieldParser is an easy and simple parser for reading CSV files using C#. It provides methods, and properties for parsing files like delimited (CSV), and Fixed width files easily. You don’t really need to use any third-party software etc as it comes built into .NET Core 3.0+ as default.

Please bookmark this page and share it with your friends. Please Subscribe to the blog to receive notifications on freshly published(2024) best practices and guidelines for software design and development.