How to inheritance a window Form from another window Form in C#.Net

Question

I am trying to inheritance a window form from another window form in C#.Net, but got Errors

My First From

   public partial class Checkout : Form
{
    public Checkout()
    {
        InitializeComponent();
       
    }
    


    private void textBox3_TextChanged(object sender, EventArgs e)
    {

    }

}

2nd From Code to which i want to make inherited Form of First Form

public partial class OnwerPermission : Checkout
    {
        public OnwerPermission()
        {
            InitializeComponent();
        }
}

Got this error

Answer 1

You can try doing this:

1. Close all the UI design pages
2. Clean Solution
3. Rebuild Solution
4. Try to open your form again