Manual Scroll Panel in a Panel or UserControl with AutoScroll=false
Manual Scroll Panel in a Panel or UserControl with AutoScroll=false
Introduction
This article show how to customize aSystem.Windows.Forms.Panel or a System.Windows.Forms.UserControl to use effectively scrollbars (ScrollProperties) without setting the AutoScroll property (you must not set AutoScroll=true). In most cases, you can use the AutoScroll = true. But in some cases, when you must work with two panels and separate Scrollbars, then you can use this ManualScrollPanel control. For example: if you will show 24 pictures just one by one on a scrollable panel, then you can set the Minimum of the VScrollProperties to 1 and the Maximum to 24. You can change Enable or Visible property of each scrollbar of the panel, receive a scrolling event, and change and receive the positions of both scrollbars.
Background
The Codeproject article "Customize a panel with Autoscroll property" by Manalee software gives the inspiration.Using the Code
In your solution, add the file ManualScrollPanel.cs to your C# project. Then you can change type of a panel in your project by theManualScrollPanel type. Now you can set the ScrollProperties values to the ManualScrollPanel (Enabled, Minimum, Maximum, SmallChange, LargeChange, Value, Visible) like you want.
In the example with the Form, you can see how the scroll is working.
Explanations about code in the ManualScrollPanel class:
First you must create a new class that overrides the System.Windows.Forms.Panel. In the constructor code, you must set the protected properties HScroll and VScroll to true. It is not possible to do this later on. You also must override the WndProc function to receive API32 scrolling messages (WM_HSCROLL, WM_VSCROLL). These messages must not pass to the base class. In WndProc was done a calculation for the new scroll value. If there is a new value then the ScrollEvent of the ManualScrollPanel was thrown.
That's all, enjoy with it in the hope that it will be useful for you...