![]() The new project has a single form ("Form1") all ready for you to use. Give the project any name you want in the Name field, and then click OK. The New Project form appears, as shown in Figure 7-2.įigure 7-2. Start Visual Studio and select New Project. Designing Windows Forms ApplicationsĬreating a Windows Forms application in Visual Basic is easy. I'll list the specific controls a little later in this chapter, and indicate which ones are not user interface controls. ![]() These controlssuch as the "Timer" controlinclude no user interface experience, but do provide a programming experience that is similar to that of the visible controls. NET (and also with the older Visual Basic) don't actually implement on-screen window elements. ![]() Both forms and controls derive from the common class, which abstracts the core Windows "window" functionality. ![]() If you don't believe me, check out the classes for the various forms and controls in. NET, as in older versions of Visual Basic, windows are grouped into "Forms" and "Controls." But they are still all windows, built from the same core components. You could commandeer any of these components and control the whole ball of wax yourself, but you'll soon find out that the Windows Forms development process is so pleasant, you will work hard to forget what "message pump" even means. The message pump is found in the .Run method. Each window-specific class includes a WndProc method that you can override and craft yourself. If you really want to, you can still access the message pump and the various WndProc routines. Many of these classes implement specific types of windows, such as ordinary main windows, buttons, text boxes, drop-down combo box lists, and so on. All of its classes appear in the namespace. It bundles up all this power and simplicity in a technology called Windows Forms. NET Framework uses a system that is quite similar to that of older Visual Basic implementations, having the WndProc call custom event handlers written by you. Microsoft did try to mask some of the tedium with a variety of technologies, including "Message Crackers" and "MFC." It was Visual Basic that finally succeeded in burying the complexity under a programmer-friendly logical system. Take it from someone who used to write Windows applications in the 'C' language: Writing message pumps and window procedures isn't a lot of fun. We set timer Interval property as 1000 milliseconds ( 1 second) and in run time the Timer will execute 10 times its Tick event. So we start the Timer in the Form_Load event and stop the Timer after 10 seconds. In this example we run this program only 10 seconds. Here is an example for start and stop methods of the Timer Control. The Timer Control has a start and stop methods to perform these actions. We can control the Timer Control Object that when it start its function as well as when it stop its function. Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick After drag and drop the Timer Control in the designer form, double click the Timer control and set the to Label control text property. Here in this program, we can see the Label Control is updated each seconds because we set Timer Interval as 1 second, that is 1000 milliseconds. For doing this, we need one Label control and a Timer Control. ![]() The following program shows a Timer example that display current system time in a Label control. The Timer Control starts its functioning only after its Enabled property is set to True, by default Enabled property is False. For example, if we want to set an interval of two minute we set the value at Interval property as 120000, means 120x1000. The Timer Control allows us to set Interval property in milliseconds (1 second is equal to 1000 milliseconds). With the Timer Control, we can control programs in millisecond, seconds, minutes and even in hours. At runtime it does not have a visual representation and works as a component in the background. The Visual Studio toolbox has a Timer Control that allowing you to drag and drop the timer controls directly onto a Windows Forms designer. As well as to start a process at a fixed time schedule, to increase or decrease the speed in an animation graphics with time schedule etc. If you want to run some code after a certain interval of time continuously, you can use the Timer control. We can use Timer Control in many situations in our development environment. By using this Timer Control, windows allow you to control when actions take place without the interaction of another thread. Timer Control plays an important role in the Client side programming and Server side programming, also used in Windows Services. ![]()
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