Develop Reference

C# winform panel not showing scrollbar

I've already seen similar questions but still could not get it to work
I have the following controls on my Form (refer image):
A: a groupbox
B: another groupbox
C: a panel which contains A and B
Height of the panel is adjusted on window resize. I have tried using Autoscroll = true on the panel but the scrollbars won't show.
The groupbox A is anchored to Top Left and has dock Top. The groupbox B is anchored to Top Leftbut has dockFill`.
Any idea why the scrollbar isn't showing ?? Also, What dock property should I give to new controls ( groupbox, maybe ), if I plan on adding more of them. I would want to show them one below the other.

Make your GroupBoxes To dock Top both. and turn autoscroll on true for your panel. That way they will stack on each other expanding themselfs down and ignoring the panel height. Also set a minheight and minwidth for both so if the panel gets to small it will start so overflow and show the scrollbars.

PictureBox anchor not working properly

On my form I have a Panel control that contains a PictureBox control and a Label control.
The panel is not visible in the image above but it's basically the area around these two controls.
I have set the Anchor property of all these three controls to Top, Bottom, Left, Right so that they follow their parent container's re-sizing behavior.
The L abel control (postbagfolderempty) works properly but the PictureBox (EMPTY!) does not seem to be moving from its original position.
Is there an additional property I need to set?
Update: I changed my PictureBox's AutoSize property to None. It has started to move, but as I try to enlarge my form, it starts sinking into a white area (image below).

Make sure your PictureBox doesn't have SizeMode set to AutoSize.
Anchoring changes the size, if it's autosized it won't change anything
Also, make 100% sure your PictureBox is actually a child of the panel. It's easy to check: select it on the designer and press Esc, it should select the panel.
Update
As per the comments, seems the problem is that you are anchoring to all the sides (thus producing the scaling of the control).
If you want a panel that scales with the form, and controls within the panel that are centered but not scaled along, then anchor that panel to all sides, place the controls inside the panel centered in the designer, and set their anchors to None, that way they won't scale, and since they are not anchored, they will move along when the panel scales (but they won't scale with it, which -seems- it's what you are aiming at)

C# FlowLayoutPanel scrollBar

I'm making an instant messaging application in C#. The problem that I'm facing right now is that for the contacts list I've made a custom control extendinguserControl, which contains aFlowLayoutPanel`.
That panel will contain a list of userControls. I want to customize the VscrollBar, but no chance (not possible). Instead I have this genius idea to hide the VscrollBar from the FlowLayoutPanel, and make simple buttons (UP and down events). For this everything worked like a charm, but when I tried to hide the VscrollBar by making the property autoScroll = false , the buttons stopped working.
How can I hide the VscrollBar?

If you want to hide the the vertical bar, there are some possible solutions. ..
You could make an event for resize, controls add, controls remove and set all the child controls' width to flowlayoutpanel.width -20
You could add a panel to the flowlayoutpanel and set it to autosize and make the panels may width to flowlayoutpanel.width-20.
You could check if the width of the flowlayoutpanel is bigger than its real width (means vscrollbar appeared) , and resize the children that it'll/ld hide again
and if you are sure that your controls are smaller than the flowlayoutpanel's width, you simply could create a panel which covers the vertical bar. (use .BringToFront() to put it before the flowlayoutpanel's scrollbar)
I hope that I understood and perhaps have solved the problem

Scrollable Form in c#, AutoScroll=true doesn't work

What are the rules which I have to respect to make the Form scrollable...
I simple set the Property AutoScroll to true.
I also tried while Auto Scroll is true, to set AutoSize to true/false, but none of these worked... also tried to put Panel and added all components in there... still nothing...
Maybe using V or HScrollBar can help, but i really don't know how to link it with the Form...
form.AutoScroll = true;
formMainLayout.AutoScroll = true;
rootPanel.AutoScroll = true;

The content controls the scrolling. The scrollbars do not appear unless they are needed. Usually, there is a property available that you can set to force them to be visible always, and simply disabled until needed.
The AutoScroll property must be true, as you have already found. But then the content of the scrollable control must force the parent control to display the scrollbars. This part is up to how the controls are embedded within the parent.
Try these two experiments:
Place a Panel on your form and dock it to Fill. Set the AutoScroll property of the Panel to true. Into that panel, place a TextBox and set it to dock as Fill as well. Also set MultiLine to true. Run the application, and you will notice that the size of both is simply using the available space...no scrolling can occur because neither the Panel, nor its TextBox become larger than the space they occupy.
Perform the same steps as in #1, but this time, do not dock the TextBox. Instead, set it to a large size, something that you know will be larger than the amount of Panel that is visible. Running the application should now produce a scrolling Panel.
Hopefully this little test helps to demonstrate what is controlling the scroll on a form.

I was also having the same problem, I managed to fix it...
All the child controls inside the panel had a Left & Right anchor, and when I only set the anchor to Top, the scrollbars where working fine.
I am not sure as to why the Left and Right anchor (of the child controls) forces the panel not to show scrollbars.
But anyways... hope this will help anyone as of this date.

The AutoScroll property should work fine, but most likely you are not using it right: the bar appears only when required. Example: minimum Y of the Form is 0 and minimum Y of one of the controls in it (a TextBox) is -20.
If you want to include a scroll bar no matter what (controls inside the boundaries of the form or not), you can also do it. Sample code (from MSDN) for a vertical scroll bar:
// Create and initialize a VScrollBar.
VScrollBar vScrollBar1 = new VScrollBar();
// Dock the scroll bar to the right side of the form.
vScrollBar1.Dock = DockStyle.Right;
// Add the scroll bar to the form.
Controls.Add(vScrollBar1);

You need to set the properties for the parent panel.
Dock = Fill
Anchor = Top, Left
AutoScroll = true
That's it. Good luck! ^^

note its for vertical scroll
Turn On auto scroll property of your Form. insert one panel and
set panel width to the form width and panel height
equal to length of your total content or may be 1300 or 1500 as
required.
Place panel location as you want set panel anchor
property to top. place your all
content inside panel.
hope it will solve your problem

I had the same problem.
You have to add only this:
this.AdjustFormScrollbars(true);

Adding a vertical scrollbar to a panel if drawn area is too large

I'm using WinForms and C#.
The application I am developing draws rows of rectangles (using g.DrawRectangle()) inside of a panel. The panel can hold 6 rectangles in width (I don't want to have horizontal scrolling). I control this within the application by counting the rectangles in the row, and then adding to the y value after the sixth rectangle.
Vertically, I want to be able to add infinite rectangles and scroll down to see them. Right now, the rectangles are being added, but the Panel doesn't scroll (they are just added off screen).
Is there a way to add a vertical scrollbar? I have tried setting the AutoScroll property to true, but that doesn't do anything.

The problem is that you are using graphics to draw on the panel. These are not controls, so they don't cause the panel to grow. you should create two panels - PanelA contains PanelB. PanelA has AutoScroll=true, but you draw on PanelB. As you draw, you also set the height of PanelB, so that when it gets bigger than PanelA, PanelA gets a scroll bar.