C#

using System;
using System.Windows.Forms;
using System.Data;
using System.Collections.Generic;
using System.ComponentModel;

namespace WindowsApplication102
{
  public partial class Form1 : Form
  {
    public Form1() { InitializeComponent(); } // Fügen Sie ein DataGridView zur Form hinzu

    private void Form1_Load(object sender,EventArgs e)
    {
      Person[] personen = new Person[]{new Person("Frank",42),        
        new Person("Eva",34), new Person("Luca",2)};

      //Bei generischer Semantik die oberen Zeilen auskommentieren etc.
      //List<Person> personen = new List<Person>(new Person[]{new Person("Frank",42), 
      //   new Person("Eva",34), new Person("Luca",2)});       

      dataGridView1.DataSource = personen; this.Width = 300;
    }

    public class Person
    {
      private string name;
      private int alter;
      private DateTime geburtstag;

      public override string ToString()
      {
        return (name);
      }

      public Person(string name,int alter)
        : this(name,alter,DateTime.Now.AddYears(-alter)) { }
      public Person(string name,int alter,DateTime geburtstag)
      {
        this.Name = name;
        this.Alter = alter;
        this.geburtstag = geburtstag;
      }

      [DisplayName("MeinName")] // im DataGridView wird "MeinName" dargestellt             
      public string Name
      {
        get { return name; }
        set { name = value; }
      }

      [Browsable(false)] // Eigenschaft wird im DataGridView nicht angezeigt
      public int Alter
      {
        get { return alter; }
        set { alter = value; }
      }

      public DateTime Geburtstag
      {
        get { return geburtstag; }
        set { geburtstag = value; }
      }
    }
  }
}

Create backups of everything - just in case!
Open the project that is compiled to the exe.
In that solution, choose Add Existing Project for each of the projects that compile to dll and add each one.
Create folders with the same names as the dll projects in the exe one.
Select all files in each dll project and drag and drop to the respective folder.
Remove the dll projects from the solution.

PC17 wrote:

must be in the same folder otherwise the program doesn´t work

PC17 wrote:

That i can use it for more things