Запись строк в файл при помощи StreamWriter

Вот без сериализации, используя ToString()

class Person
{
    public int Age { get; set; }
    public string Name { get; set; }
    public string WorkPlace { get; set; }
    public override string ToString()
    {
        return $"Имя: {this.Name},{Environment.NewLine}Возраст: {this.Age},{Environment.NewLine}Рабочее место: {this.WorkPlace}";
    }
}
class Program
{
    static void Main(string[] args)
    {
        Person person = new Person()
        {
            Age = 31,
            Name = "Вася",
            WorkPlace = "Цех самоубийц"
        };
        string path = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments);
        path = Path.Combine(path, "people.txt");
        using (FileStream fs = File.OpenWrite(path))
        using (StreamWriter sw = new StreamWriter(fs))
        {
            sw.Write(person.ToString());
        }
    }
}