How to get ALL child controls of a Windows Forms form of a specific type (Button/Textbox)?

user_270631 0
Viewed 230929

I need to get all controls on a form that are of type x. I'm pretty sure I saw that code once in the past that used something like this:

dim ctrls() as Control
ctrls = Me.Controls(GetType(TextBox))

I know I can iterate over all controls getting children using a recursive function, but is there something easier or more straightforward, maybe like the following?

Dim Ctrls = From ctrl In Me.Controls Where ctrl.GetType Is Textbox
controls vb.net winforms .net c#
28 Answers

It might be the ancient technique, but it works like charm. I used recursion to change the color of all labels of the control. It works great.

internal static void changeControlColour(Control f, Color color)
{
    foreach (Control c in f.Controls)
    {

        // MessageBox.Show(c.GetType().ToString());
        if (c.HasChildren)
        {
            changeControlColour(c, color);
        }
        else
            if (c is Label)
            {
                Label lll = (Label)c;
                lll.ForeColor = color;
            }
    }
}
user_11324230

You can use the below Code 

public static class ExtensionMethods
{
    public static IEnumerable<T> GetAll<T>(this Control control)
    {
        var controls = control.Controls.Cast<Control>();

        return controls.SelectMany(ctrl => ctrl.GetAll<T>())
                                  .Concat(controls.OfType<T>());
    }
}
user_117262420

Create Method

public static IEnumerable<Control> GetControlsOfType<T>(Control control)
{
    var controls = control.Controls.Cast<Control>();
    return controls.SelectMany(ctrl => GetControlsOfType<T>(ctrl)).Concat(controls).Where(c => c is T);
}

And use it Like

Var controls= GetControlsOfType<TextBox>(this);//You can replace this with your control
user_69473850

I'm saldy using VB so, I wrote an extension method. That retrieve all children and sub children of a control

Imports System.Runtime.CompilerServices
Module ControlExt

<Extension()>
Public Function GetAllChildren(Of T As Control)(parentControl As Control) As IEnumerable(Of T)
    Dim controls = parentControl.Controls.Cast(Of Control)
    Return controls.SelectMany(Of Control)(Function(ctrl) _
        GetAllChildren(Of T)(ctrl)) _
        .Concat(controls) _
        .Where(Function(ctrl) ctrl.GetType() = GetType(T)) _
    .Cast(Of T)
End Function

End Module

Then you can use it like, where "btnList" is a control

btnList.GetAllChildren(Of HtmlInputRadioButton).FirstOrDefault(Function(rb) rb.Checked)

In this case, it will select the selected radio button.

user_47984590

I modified from @PsychoCoder. All controls could be found now (include nested).

public static IEnumerable<T> GetChildrens<T>(Control control)
{
  var type = typeof (T);

  var allControls = GetAllChildrens(control);

  return allControls.Where(c => c.GetType() == type).Cast<T>();
}

private static IEnumerable<Control> GetAllChildrens(Control control)
{
  var controls = control.Controls.Cast<Control>();
  return controls.SelectMany(c => GetAllChildrens(c))
    .Concat(controls);
}
user_13222120 
    public static IEnumerable<T> GetAllControls<T>(this Control control) where T : Control
    {
        foreach (Control c in control.Controls)
        {
            if (c is T)
                yield return (T)c;
            foreach (T c1 in c.GetAllControls<T>())
                yield return c1;
        }
    }
user_12668730

VISUAL BASIC VB.NET For some of us, who refuse to port 230,000+ lines of code to c# here is my contribution, if only an specific type required, just add a 'where' as needed.

Private Shared Function getAll(control As Control) As IEnumerable(Of Control)
    Return control.Controls.Cast(Of Control) _
        .SelectMany(Function(f) getAll(f).Concat(control.Controls.Cast(Of Control)))
End Function
user_44495160

Simply:

For Each ctrl In Me.Controls.OfType(Of Button)()
   ctrl.Text = "Hello World!"
Next
user_21080090
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