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Form.StartPosition Property

Gets or sets the starting position of the form at run time.

Namespace:  System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)

public FormStartPosition StartPosition { get; set; }

Property Value

Type: System.Windows.Forms.FormStartPosition
A FormStartPosition that represents the starting position of the form.


The value specified is outside the range of valid values.

This property enables you to set the starting position of the form when it is displayed at run time. The form’s position can be specified manually by setting the Location property or use the default location specified by Windows. You can also position the form to display in the center of the screen or in the center of its parent form for forms such as multiple-document interface (MDI) child forms.

This property should be set before the form is shown. You can set this property before you call the Show or ShowDialog method or in your form's constructor.

The following code example creates a new instance of a Form and calls the ShowDialog method to display the form as a dialog box. The example sets the FormBorderStyle, AcceptButton, CancelButton, and StartPosition properties to change the appearance and functionality of the form to a dialog box. The example also uses the Add method of the form's Controls collection to add two Button controls. The example uses the HelpButton property to display a help button in the caption bar of the dialog box.

public void CreateMyForm()
    // Create a new instance of the form.
    Form form1 = new Form();
    // Create two buttons to use as the accept and cancel buttons.
    Button button1 = new Button ();
    Button button2 = new Button ();

    // Set the text of button1 to "OK".
    button1.Text = "OK";
    // Set the position of the button on the form.
    button1.Location = new Point (10, 10);
    // Set the text of button2 to "Cancel".
    button2.Text = "Cancel";
    // Set the position of the button based on the location of button1.
       = new Point (button1.Left, button1.Height + button1.Top + 10);
    // Set the caption bar text of the form.   
    form1.Text = "My Dialog Box";
    // Display a help button on the form.
    form1.HelpButton = true;

    // Define the border style of the form to a dialog box.
    form1.FormBorderStyle = FormBorderStyle.FixedDialog;
    // Set the accept button of the form to button1.
    form1.AcceptButton = button1;
    // Set the cancel button of the form to button2.
    form1.CancelButton = button2;
    // Set the start position of the form to the center of the screen.
    form1.StartPosition = FormStartPosition.CenterScreen;

    // Add button1 to the form.
    // Add button2 to the form.

    // Display the form as a modal dialog box.

.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.