C# Windows Forms - ComboBox - Fill From ArrayList

February 2, 2018 Oclemy C# ComboBox, C# ArrayList 1 minute, 21 seconds

Let's see how to fill our ordinary windows forms combobox control with an arraylist of data.

We then see display a messagebox when our combobox items are seected.

Example Demo

What is a ComboBox

A combobox is a User Interface control that displays items in a dropdown menu.

ComboBoxes allow users to select one item at a time.

Why ComboBox?

No. Advantage
1. ComboBox display lists of items in a small space.
2. ComboBox allow users to select one item at a time.
3. ComboBox allows us to handle IndexSelectionChanged events.

Let's go.

1. Create Empty Project

  1. Open up Visual Studio and proceed over to File --> New Project

  2. A new dialog popus up like this:

Create Project

  1. Give our empty project a name and click OK. An empty project will get generated for us.

2. Make project a Windows Project

Just right click on your project choose properties and set output type to Windows Application:

MetroFramewok References

3. Progam.cs

Create a class Program.cs. It is our main class with our main method. This is the only class we have.

using System;
using System.Collections;
using System.Drawing;
using System.Windows.Forms;

namespace ComboBoxArrayList
    static class Program
        private static ComboBox comboBox;
        public static void Main()
            Form myForm = new Form
                Text = "WinForms ComboBox - ArrayList",
                ClientSize = new Size(564, 420)

            comboBox = new ComboBox { Location = new Point(164, 176),DropDownStyle = ComboBoxStyle.DropDownList};
            ArrayList nebulae = new ArrayList { "Horse Head", "Black Widow", "Ghost Head", "Cat's Eye", "Helix", "Rosette", "Ant", "Orion", "Butterfly", "Eagle", "Own", "Ring", "Pelican", "Witch Head", "Bumerang" };
            comboBox.DataSource = nebulae;

            comboBox.SelectedIndexChanged += comboBox_SelectedIndexChanged;


        static void comboBox_SelectedIndexChanged(object sender, EventArgs e)

Best Regards, Oclemy.