drag and drop system designer that generate codes

#DRAG AND DROP SYSTEM DESIGNER THAT GENERATE CODES HOW TO#
#DRAG AND DROP SYSTEM DESIGNER THAT GENERATE CODES CODE#
#DRAG AND DROP SYSTEM DESIGNER THAT GENERATE CODES WINDOWS#

You can now press F5 to test the application. In addition, you will also change the border style of the TextBox control to FixedSingle so that it serves as a visual cue to the user (Listing 1 ). To check for this special keystroke, you use the KeyState property together with a Control Mask (defined as a byte with a value of 8).

Here, you will determine if the operation is copy or move, and then set the mouse pointer accordingly. As mentioned earlier, the control fires this event when you drag something into the TextBox control. The next event to service is the DragEnter event. In the Form1_Load event, set its AllowDrop property to True: Private Sub Form1_Load( _

#DRAG AND DROP SYSTEM DESIGNER THAT GENERATE CODES CODE#

Switch to the code behind of Form1 and declare the following constant: Public Class Form1

On the default Form1, populate it with a TextBox control and set its properties as follows ( Figure 2): Figure 2: TextBox control in Form1. As such, you need to dynamically set them in code (note that IntelliSense will not show the AllowDrop property). However, some controls (such as the PictureBox control) do not expose this property in the Properties window. For most controls, you can set the AllowDrop property in the Properties window during design time.

#DRAG AND DROP SYSTEM DESIGNER THAT GENERATE CODES HOW TO#

For this section, I’ll show you how to drag and drop some text into a TextBox control.

#DRAG AND DROP SYSTEM DESIGNER THAT GENERATE CODES WINDOWS#

Using Visual Studio 2005, create a new Windows Forms application and name it DragAndDrop. I’ll now create a Windows Forms application so that you can examine how you can implement drag and drop. In this case, you will have to use other supported events to detect drag and drop, such as the DragEnter event. For example, the RichTextBox control does not support the DragOver event. Note that not all controls support the entire set of events just described. In the above example, you will load the right PictureBox control with the image that the user drags from the left PictureBox control.

In this event you can modify the target control so that it accepts the dropped item. When the mouse drops over the control to be dropped upon, the control fires the DragDrop event. You usually service this event if you need to modify the appearance of the target control to reflect that it is a drop target. When the mouse leaves the control to be dropped upon, the control fires the DragLeave event. You can either use this event or the DragEnter event to change the appearance of the mouse pointer. The control fires this event continuously as long as the mouse is over the target control. When the mouse hovers over the control to be dropped upon, the control fires the DragOver event. You can also modify the appearance of the control so that it is obvious to the user that the control is a drop target. This is usually the event that you need to service to change the mouse pointer to reflect the action it is performing (such as copy, move, etc). When the mouse enters the control to be dropped upon, the control fires the DragEnter event. On the control to be dropped upon (right PictureBox control): You can handle this event if you wish to modify the appearance of the mouse pointer. The control constantly fires the GiveFeedBack event during the drag operation. You can call the DoDragDrop() method either in the MouseDown or the MouseMove event.

If the dragging is a move operation and the user successfully executes it, you may need to remove the image on the left PictureBox control. The Quer圜ontinueDrag event allows you to know the outcome of the drag operation, i.e., whether the user eventually drops the item. In this case, you will copy the image stored in the left PictureBox control. The MouseDown/MouseMove event is probably a good starting point to load the data that is going to be dragged. On the control to be dragged (left PictureBox control): Figure 1: Dragging an image from one PictureBox control to another. Consider the example of Figure 1 where you drag an image displayed in a PictureBox control to another PictureBox control. To understand how you can drag objects from one control onto another control, you need to become acquainted with a couple of event handlers. In this article, I will show you how to implement drag and drop functionality in your Windows Forms application. While it does take considerable effort to implement, the support for drag and drop in your application will greatly increase its usefulness. However, not many developers take the effort to implement drag and drop functionality in their applications. Using a mouse you can drag and drop a file from one location to another or you may drag a file and drop it onto an application to launch it. One of the important features of Graphical User Interfaces (GUI) is drag and drop.

Drag and drop system designer that generate codes