How can I get all controls from a Form Including controls in any container?

Question

I need, for example, a way to disable all buttons in a form or validate all textboxes' data. Any ideas? Thanks in advance!

Answer 1

The simplest option may be to cascade:

public static void SetEnabled(Control control, bool enabled) {
    control.Enabled = enabled;
    foreach(Control child in control.Controls) {
        SetEnabled(child, enabled);
    }
}

or similar; you could of course pass a delegate to make it fairly generic:

public static void ApplyAll(Control control, Action<Control> action) {
    action(control);
    foreach(Control child in control.Controls) {
        ApplyAll(child, action);
    }
}

then things like:

ApplyAll(this, c => c.Validate());

ApplyAll(this, c => {c.Enabled = false; });

Answer 2

I prefer a lazy (iterator) approach to the problem, so this is what I use:

/// <summary> Return all of the children in the hierarchy of the control. </summary>
/// <exception cref="ArgumentNullException"> Thrown when one or more required arguments are null. </exception>
/// <param name="control"> The control that serves as the root of the hierarchy. </param>
/// <param name="maxDepth"> (optional) The maximum number of levels to iterate.  Zero would be no
///  controls, 1 would be just the children of the control, 2 would include the children of the
///  children. </param>
/// <returns>
///  An enumerator that allows foreach to be used to process iterate all children in this
///  hierarchy.
/// </returns>
public static IEnumerable<Control> IterateAllChildren(this Control control,
                                                      int maxDepth = int.MaxValue)
{
  if (control == null)
    throw new ArgumentNullException("control");

  if (maxDepth == 0)
    return new Control[0];

  return IterateAllChildrenSafe(control, 1, maxDepth);
}


private static IEnumerable<Control> IterateAllChildrenSafe(Control rootControl,
                                                           int depth,
                                                           int maxDepth)
{
  foreach (Control control in rootControl.Controls)
  {
    yield return control;

    // only iterate children if we're not too far deep and if we 
    // actually have children
    if (depth >= maxDepth || control.Controls.Count == 0)
      continue;

    var children = IterateAllChildrenSafe(control, depth + 1, maxDepth);
    foreach (Control subChildControl in children)
    {
      yield return subChildControl;
    }
  }
}

Answer 3

Also try:

public List<Control> getControls(string what, Control where)
    {
        List<Control> controles = new List<Control>();
        foreach (Control c in where.Controls)
        {
            if (c.GetType().Name == what)
            {
                controles.Add(c);
            }
            else if (c.Controls.Count > 0)
            {
                controles.AddRange(getControls(what, c));
            }
        }
        return controles;
    }

    private void Form1_Load(object sender, EventArgs e)
    {
        var c = getControls("Button", this);

    }