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C# TreeView disable scrolling in UserControl [duplicate]

I have a little problem with winforms and mousewheel events.
I have a custom user control representing a slider. Now, I have a couple groups of sliders in which each group is wrapped inside a panel. All the groups are then wrapped in another panel (which has AutoScroll set to true) and this is wrapped in a form. The slider logic is implemented such that the mousewheel can be used to change its value. For this, the slider user control gets focus when the mouse is over the slider. However, when I scroll, also the AutoScroll parent panel scrolls with it.
I've already lost a lot of time on this issue. Anybody knows what is happening here and how I can solve it? I thought the event was bubbling to the parent panel but I don't find a Handled property on the event when handling it in the Slider control (as is possible with WPF).
many thanks

We implemented the Slider as a complete custom user control (inheriting the UserControl class) with own look-and-feel.
You might have noticed that a UserControl doesn't show the MouseWheel event in the Properties window. Hint of trouble there. The WM_MOUSEWHEEL message bubbles. If the control that has the focus doesn't handle it then Windows passes it on to its Parent. Repeatedly, until it finds a parent window that wants to handle it. The Panel in your case.
You'll need to invoke a bit of black magic in your slider control. The actual event args object that get passed to the MouseWheel event is not of the MouseEventArgs type as the event signature suggests, it is HandledMouseEventArgs. Which lets you stop the bubbling. Like this:
protected override void OnMouseWheel(MouseEventArgs e) {
base.OnMouseWheel(e);
// do the slider scrolling
//..
((HandledMouseEventArgs)e).Handled = true;
}

If you are creating event dynamically like
object.event += new EventHandler<EventArgs>(eventfunction);
try un-registering the event after the eventfunction is called like this
object.event -= new EventHandler<EventArgs>(eventfunction);

Handling PointerEntered and PointerReleased but passing Click/Tap to parent element

I have a Grid and inside the grid, I have Buttons. I need PointerEntered and PointerReleased events as I need to track which buttons are hovered. The problem is that, I need my Grid to handle the click events. Even though I don't have a click/tap/press handler for the button, my button captures the click and doesn't bubble it up to its parent (Grid). If I disable the button by settin IsEnabled to false, the click event is bubbled up to the Grid correctly, but then PointerEntered and PointerReleased events aren't fired, which I need to handle on the button. How can I handle enter/release events on the button and at the same time, pass the click event to its parent? I need my Grid to go onto "clicked" state as I also listen for the PointerReleased event on it. If click doesn't fire, released doesn't fire even if I do release the mouse button when on the Grid.
Thanks,
Can.

Try using AddHandler to attach a click event to grid and see if it works for you.
http://msdn.microsoft.com/en-us/library/windows/apps/windows.ui.xaml.uielement.addhandler.aspx
Remember to remove the event using RemoveHandler when done.

Enter event not firing in Panel inside a UserControl

I added a Panel inside a UserControl i design time.
Then, I added this control to a form.
I want to show a focus dashed border when the control has the focus.
Unfortunately, the Enter event from the panel never fires. I only get a fire when I click on the user control itself.
To extend this question. How can I forward events from controls inside a user control to the base user control? A comment from Hans Passant in this question says that by default events are forwarded to their direct parent. I didn't change any of the control's properties. What am I doing wrong? Is there an obvious property I need to change on each control i order to force it to forward unhandled events?
I am using DevExpress controls but this behavior is same in windows WinForms controls.
edit: I understand that panel might not be able to get focus. If this is true, how do I forward each mouse event to the parent control?

Based on your comment, from inside your UserControl, handle the panel's MouseDown event and set the focus to the parent control:
public UserControl1() {
InitializeComponent();
panel1.MouseDown += new MouseEventHandler(panel1_MouseDown);
}
void panel1_MouseDown(object sender, MouseEventArgs e) {
if (!this.Focused)
this.Focus();
}

Use panel1.Select() on MouseClick event of the panel and you will be able to trigger panel1.Enter and panel1.Leave

C# WinForms dragging controls with mouse

I'm making a calendar From in C# using WinForms.
I've put it together using a two-dimensional array of Panels, and inside them I have a List<> of custom controls which represent appointments.
The user needs to be able to drag appointment controls from one Panel to another (from day to day).
The custom control has a MouseDown and MouseUp event, which passes a message up from the control to the Parent.Parent (custom control -> day panel -> calendar form) and calls public methods StartDragging() and StopDragging() respectively.
Inside these methods, I make a clone of the custom control and add it to the Form, and store it in a global variable in the form which is called DraggedControl.
The Form has an event handler for MouseMove which goes like this:
void Calendar_MouseMove(object sender, MouseEventArgs e)
{
if (DraggedControl == null)
return;
DraggedControl.Location = PointToClient(MousePosition);
Refresh();
}
There are two problems, however:
First of all, the custom control is under everything else. I can see it being added and removed on MouseDown and MouseUp, but it is being added at 0,0 under the panels and day Labels.
Secondly, it does not appear to be moving with the MouseMove at all. I have a feeling this might be because I am moving the mouse with the button pressed, and this would represent a drag action rather than a basic MouseMove.
If I remove the MouseUp code, the control does drag with the mouse, however as soon as the mouse enters the panels (which the control is, sadly, underneath), the drag action stops.
What would you suggest I do?
I suspect there is probably a better way to do what I am trying to do.

custom control is under everything
else
bring it on top:
DraggedControl.BringToFront();
it does not appear to be moving with
the MouseMove at all
Control, which handled MouseDown event, captures mouse input and receives all following MouseMove events until it releases mouse input on MouseUp event, that's why Calendar_MouseMove() is not called. Handle MouseMove event for the same control, which generated MouseDown event.

Can't see MouseWheel even on nested Panel control in C#

I have a Panel on a TabPage on a TabControl that is on a form.
I have a Mouse Event function "control_MouseWheel".
If I bind that function to the MouseWheel event of just the panel, nothing happens when I scroll the mousewheel.
If I bind that function to the MouseWheel event of both the panel and the TabPage or all three of the Panel, the TabPage and the TabControl, nothing happens.
If I then bind that function to the MouseWheel event of the form, the mouse event handler fires, but only on the form. I can see this via the use of ConsoleWriteline().
How do I get it to fire for the underlying panel that I actually want to use the mouse wheel event?
Am I missing a property setting for the stack of child controls?

The MouseWheel event is sent to the control that has focus.
Since panels cannot have focus, they will never get MouseWheel events.