Form.StartPosition 属性

定义

命名空间:

System.Windows.Forms

程序集:

System.Windows.Forms.dll

获取或设置运行时窗体的起始位置。

public:
 property System::Windows::Forms::FormStartPosition StartPosition { System::Windows::Forms::FormStartPosition get(); void set(System::Windows::Forms::FormStartPosition value); };

public System.Windows.Forms.FormStartPosition StartPosition { get; set; }

member this.StartPosition : System.Windows.Forms.FormStartPosition with get, set

Public Property StartPosition As FormStartPosition

属性值

FormStartPosition

FormStartPosition，表示窗体的起始位置。

例外

InvalidEnumArgumentException

指定值不在有效值范围内。

示例

以下示例创建一 Form 个新实例，并调用该方法 ShowDialog 以对话框形式显示窗体。 本示例设置窗体的外观和功能更改为对话框的属性FormBorderStyleCancelButtonAcceptButton。StartPosition 该示例还使用 Add 窗体 Controls 集合的方法添加两 Button 个控件。 该示例使用 HelpButton 该属性在对话框的标题栏中显示帮助按钮。

public:
   void CreateMyForm()
   {
      // Create a new instance of the form.
      Form^ form1 = gcnew Form;
      // Create two buttons to use as the accept and cancel buttons.
      Button^ button1 = gcnew Button;
      Button^ button2 = gcnew Button;
      
      // Set the text of button1 to "OK".
      button1->Text = "OK";
      // Set the position of the button on the form.
      button1->Location = 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.
      button2->Location
         = 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.
      form1->Controls->Add( button1 );
      // Add button2 to the form.
      form1->Controls->Add( button2 );
      
      // Display the form as a modal dialog box.
      form1->ShowDialog();
   }

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.
    button2.Location
       = 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.
    form1.Controls.Add(button1);
    // Add button2 to the form.
    form1.Controls.Add(button2);
    
    // Display the form as a modal dialog box.
    form1.ShowDialog();
 }

Public Sub CreateMyForm()
    ' Create a new instance of the form.
    Dim form1 As New Form()
    ' Create two buttons to use as the accept and cancel buttons.
    Dim button1 As New Button()
    Dim button2 As 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.
    button2.Location = 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.
    form1.Controls.Add(button1)
    ' Add button2 to the form.
    form1.Controls.Add(button2)
    
    ' Display the form as a modal dialog box.
    form1.ShowDialog()
End Sub

注解

此属性使你可以在运行时显示窗体时设置窗体的起始位置。 可以通过设置 Location 属性或使用 Windows 指定的默认位置来手动指定窗体的位置。 还可以将窗体置于屏幕中心或窗体父窗体的中心，例如多文档界面 (MDI) 子窗体。

应在显示窗体之前设置此属性。 可以在调用 Show 或 ShowDialog 方法或窗体构造函数之前设置此属性。

另请参阅

• FormStartPosition