How can I reuse this snippet throughout a project?

Question

I have this code on each form in my app that has textboxes to prevent the textboxes that are ReadOnly from being tabbed to:

private void FrmInventory_Load(object sender, EventArgs e)
{
    foreach (var txtbx in Controls.OfType<TextBox>())
    {
        txtbx.TabStop = (!txtbx.ReadOnly);
    }
}

It would be good to only have this code in one place, but how can I do that, as each time that "external" method was called, it would touch TextBoxes on the calling form, which smells a little fishy. Is an extension method the way to go, something like:

public static bool TextboxIsReadOnly(this TextBox txtbx)
{
    return txtbx.ReadOnly;
}

...and then call it like this:

foreach (var txtbx in Controls.OfType<TextBox>())
{
    txtbx.TabStop = TextboxIsReadOnly(txtbx);
}

?

That doesn't seem like it's of much value - I still would have to put most of the code in each form, just as things stand now. Creating a custom textbox that is both ReadOnly and TabStop = false seems a little overkillish...

Is there a way to have this logic execute for every TextBox-containing form, without reproducing the code all throughout the project?

Answer 1

You can create a baseForm and Inherit that form in each of your forms.

Add a new Windows Form to your project(baseForm) and create load event

 public class baseForm: Form
 {
    public baseForm()
    {
        this.Load += baseForm_Load;
    }

    void baseForm_Load(object sender, EventArgs e)
    {
      var t = GetAll<TextBoxX>(this);
      foreach (var txtbx in Controls.OfType<TextBox>())
      {
           txtbx.TabStop = (!txtbx.ReadOnly);
      }
     }

    public static List<T> GetAll<T>(Form f1)
    {
        List<T> f = new List<T>();
        try {
            if (f1 != null) {
                CheckInner<T>(f1.Controls, ref f);
            }
        } catch (Exception ex) {
            f.Clear();
        }

        return f;
    }
 }

And finally in each form you can do like this

public partial class FrmInventory : baseForm
{
}