How to use separate .cs files in C#?

Question

Forum; I am a newbie working out a bit of code. I would like to know the best way to use separate .cs files containing other classes and functions. As an example of a basic func

Answer 1

You can use a partial class for your MainForm class, since that's already being done in MainForm.cs and MainForm.Designer.cs.

btnClear.cs

public partial class MainForm
{
   private void clearForm(object sender, EventArgs e)
   {
     // ...
   }
}

And register for the event in MainForm.cs or MainForm.Designer.cs

this.btnClear.click += clearForm;

Edit:

If you want a generic way of doing it, you could set the Tag property of your controls to be the default value. And with an extension method, you could do something like formGroup.Reset();

using System.Windows.Forms;

public class ControlExtensions
{
  public void Reset(this Control control)
  {
    if (control.Tag != null)
    {
      if (control is TextBoxBase && control.Tag is string)
      {
        control.Text = control.Tag as string;
      }
      else if (control is CheckBox && control.Tag is bool)
      {
        control.Checked = control.Tag as bool;
      }
      // etc
    }

    foreach (Control child in control.Children)
      child.Reset();
  }
}