Browse by Tags

All Tags » General » Forms (RSS)

• How do I center a form?

  Set the Form's StartPosition property to CenterScreen . Contributed from George Shepherd's Windows Forms FAQ

• How do I prevent a user from moving a form?

  The following code snippet (posted in the Windows Forms FAQ forums) shows how you can prevent a user from moving a form at run time: protected override void WndProc( ref Message m ) { const int WM_NCLBUTTONDOWN = 161; const int WM_SYSCOMMAND = 274; const...

• How do I position a form at the bottom right of the screen, above the system tray, when it opens up the first time?

  Do as follows in your Form's constructor after setting the StartPosition to Manual: SetBounds( Screen.GetWorkingArea( this ).Width - Width, Screen.GetWorkingArea( this ).Height - Height, Width, Height ); Contributed from George Shepherd's Windows...

• How do I programmatically maximize or minimize a form?

  Set the System.Windows.Forms.Form.WindowState property to FormWindowState.Maximized or FormWindowState.Minimized. Contributed from George Shepherd's Windows Forms FAQ

• How do I programmatically set the initial position of a Form so that it is displayed properly on invocation through ShowDialog()?

  In addition to setting the Location property of the form, make sure you also set the StartPosition property of the form to FormStartPosition.Manual. Contributed from George Shepherd's Windows Forms FAQ

• How do I postpone the resizing controls until the form's resizing is complete?

  I have a form with several controls on it. As I size the form, the controls are being resized continuously. Is it possible to postpone changing the controls position until the resizing is complete? The idea is to do the painting on Idle. This means you...

• How do I prevent a Form from closing when the user clicks on the close button?

  Handle the form's Closing event. private void Form1_Closing( object sender, CancelEventArgs e ) { if ( NotOkToClose() ) e.Cancel = true; //don't close } Contributed from George Shepherd's Windows Forms FAQ

• How do I determine if a form was closed from the system menu or a call to Form.Close?

  One way to do this is to override the form's WndProc method and check for WM_SYSCOMMAND and SC_CLOSE. Looking for WM_CLOSE in the override is not sufficient as WM_CLOSE is seen in both cases. A sample is available for download ( C# , VB ). public...

• How do I force a Windows Form application to exit?

  Your main form is an object of type System.Windows.Forms.Form. Use its Close method to exit the application. If you wish to Exit from a Form's constructor, this will not work. A workaround is to set a boolean flag that you can later check in the Form's...

• How do I create an instance of a Form class from its name?

  You can use the System.Reflection.Assembly.CreateInstance method to create a form from its name. Below is a code snippet. The name in the textbox has to be the full name including its namespace. So if there is a class named Form2 in namespace MyCompanyName...

• How do I create a form that is 'TopMost' for only my application, but not other applications?

  You can do this by setting the child form's TopMost to False and setting its Owner property to the Main Form. Form1 f = new Form1(); f.TopMost = false; f.Owner = this; f.Show(); Contributed from George Shepherd's Windows Forms FAQ

• How do I create a non-modal top level form that always stays on top of all the app's windows?

  For example the Find dialog in Visual Studio. Make your main form the "Owner" of the form in question. Refer to Form.Owner in class reference for more information. findReplaceDialog.Owner = this; // where 'this' is the main form findReplaceDialog...

• How do I ensure that a form will always be on the desktop?

  To set or control the location of the form using desktop coordinates, you can use the SetDeskTopLocation property. You can do this by setting the child form's TopMost to False and setting its Owner property to the Main Form. this.SetDesktopLocation...

• How do I prevent a form from being shown in the taskbar?

  You need to set the form's ShowInTaskbar property to False to prevent it from being displayed in the Windows taskbar. Contributed from George Shepherd's Windows Forms FAQ

• How do I add items to the system menu of a Form?

  To do this, you can use use iterop to access the GetSystemMenu and AppendMenu Win32 APIs. You also need to override the form's WndProc method to catch and act on the menu message. This idea was posted in the Microsoft newsgroups by Lion Shi. Here...

• How do I show a form without making it active?

  Normally when you make a Form visible by setting the Visible property to true, it will show the form and set the focus too. In some cases however, you do not want it to take focus until the user clicks on it. To get this behavior, do the following utility...

• How do I access a TextBox on one Form from another Form?

  One way to do this is to make the TextBox either a public property or a public field. Then you will be able to access it through the instance of its parent form. So, if TextBox1 is a public member of FormA and myFormA is an instance of FormA, then you...

• How do I work with multiple forms since that's different from VB6?

  Check out Working with Multiple Forms in Visual Basic .NET: Upgrading to .NET by Duncan Mackenzie in the MSDN Library. Contributed from George Shepherd's Windows Forms FAQ

• How do I return values from a form?

  Add public properties to your form. Then these properties can be accessed by any object that creates an instance of your form. Contributed from George Shepherd's Windows Forms FAQ

• How do I set the default button for a form?

  Set the form's AcceptButton property. You can do this either through the designer, or through code such as form1.AcceptButton = button1; Contributed from George Shepherd's Windows Forms FAQ

• How do I get the Form's ClientRectangle position in non-client coordinates?

  I would like to use the Region property to create a form with hidden non-client areas (not exactly a rectangle), but I can't determine the client area rectangle position in non-client coordinates. The code I usually use to get this offset is: Point...