How can you write a list of objects to a CSV file manually (without a library)?

Question

ICSM Computer · Answer

To write a list of objects to a CSV file manually (without using a third-party library like CsvHelper), you can use
System.IO.StreamWriter and reflection or direct property access.
Example: Write a List of Objects to CSV
Model:
public class Person
{
    public int Id { get; set; }
    public string Name { get; set; }
    public string Email { get; set; }
}
Writing to CSV:
using System;
using System.Collections.Generic;
using System.IO;
public class CsvWriterExample
{
    public static void WriteCsv(string path, Listandlt;Personandgt; people)
    {
        using (var writer = new StreamWriter(path))
        {
            // Write header
            writer.WriteLine("Id,Name,Email");
            foreach (var person in people)
            {
                // Escape commas and quotes if necessary
                string line = $"{Escape(person.Id.ToString())},{Escape(person.Name)},{Escape(person.Email)}";
                writer.WriteLine(line);
            }
        }
    }
    private static string Escape(string field)
    {
        if (field.Contains(",") || field.Contains(""") || field.Contains("
"))
        {
            // Escape quotes and wrap in quotes
            field = field.Replace(""", """");
            return $""{field}"";
        }
        return field;
    }
}
Usage:
var people = new Listandlt;Personandgt;
{
    new Person { Id = 1, Name = "John", Email = "john@example.com" },
    new Person { Id = 2, Name = "Jane, A.", Email = "jane@example.com" }, // comma in name
};
CsvWriterExample.WriteCsv("people.csv", people);
Why Use Escape()?
CSV fields must be quoted if they contain:Commas ,Newlines 
Double quotes "Double quotes in a field must be escaped as "" and the entire field wrapped in quotes.

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How can you write a list of objects to a CSV file manually (without a library)?

ICSM Computer

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1 Answers

Example: Write a List of Objects to CSV

Model:

Writing to CSV:

Usage:

Why Use `Escape()`?

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