Instead of using the Windows Forms Designer and Toolbox as in the previous tutorial, in this tutorial you manually add a custom control to a Windows application and then write code to instantiate the control on a form. There are eight steps...

1. Create a Windows Application project called CustomTutorial:
   
    
   
2. Add a User Control class to the project:
   
    
   
3. Rename the control to RandomLabel.cs and click OK.
   
    
   
4. Change the class declaration in file RandomLabel.cs to inherit from a more specific control.  Change this:

public partial class RandomLabel : UserControl

to this:

public partial class RandomLabel : System.Windows.Forms.Label

5. Modify the code as follows (copy code from this plain text file:

      public RandomLabel()
      {
          InitializeComponent();
          Random r = new Random();
          this.Text = r.Next(100).ToString();
          this.BackColor = Color.Yellow;
      }
      

6. Add the Form1_Load event to Form1.cs; to do this, open Form1 in the designer and double-click somewhere on the form. Modify the Form1_Load method as follows (copy code from this plain text file):

      private void Form1_Load(object sender, EventArgs e)
      {
          for (int i = 0; i < 10; i++)
          {
              RandomLabel mylabel = new RandomLabel();
              this.Controls.Add(mylabel);
              mylabel.Location = new Point(15, i * 25);
              mylabel.Size = new Size(50, 20);
              System.Threading.Thread.Sleep(300);
          }
      }
      

7. Close and save both files and try to build the project. You'll probably get a compile error--just click on the error to open the code to the error location, and comment out the offending line of code as shown below and rebuild (this seems to be a bug):
   
    
   
8. Now build and run the project and you should see this (with different random numbers):
   

Visitors: