ComboBox.DropDownStyle ComboBox.DropDownStyle ComboBox.DropDownStyle ComboBox.DropDownStyle Property

定義

コンボ ボックスのスタイルを指定する値を取得または設定します。Gets or sets a value specifying the style of the combo box.

public:
 property System::Windows::Forms::ComboBoxStyle DropDownStyle { System::Windows::Forms::ComboBoxStyle get(); void set(System::Windows::Forms::ComboBoxStyle value); };
public System.Windows.Forms.ComboBoxStyle DropDownStyle { get; set; }
member this.DropDownStyle : System.Windows.Forms.ComboBoxStyle with get, set
Public Property DropDownStyle As ComboBoxStyle

プロパティ値

ComboBoxStyle 値のいずれか 1 つ。One of the ComboBoxStyle values. 既定値は、DropDown です。The default is DropDown.

例外

代入された値が、ComboBoxStyle 値ではありません。The assigned value is not one of the ComboBoxStyle values.

プロパティをDropDownStyle設定するコード例を次に示します。The following code example demonstrates setting the DropDownStyle property. この例を実行するには、フォームに次のコードを貼り付けます。To run the example, paste the following code in a form. フォームのInitializeComboBoxコンストラクターまたはLoadイベントでメソッドを呼び出します。Call the InitializeComboBox method in the form's constructor or Load event.

internal:
   System::Windows::Forms::ComboBox^ ComboBox1;

private:
   array<String^>^ animals;

   // This method initializes the owner-drawn combo box.
   // The drop-down width is set much wider than the size of the combo box
   // to accomodate the large items in the list.  The drop-down style is set to 
   // ComboBox.DropDown, which requires the user to click on the arrow to 
   // see the list.
   void InitializeComboBox()
   {
      this->ComboBox1 = gcnew ComboBox;
      this->ComboBox1->DrawMode = System::Windows::Forms::DrawMode::OwnerDrawVariable;
      this->ComboBox1->Location = System::Drawing::Point( 10, 20 );
      this->ComboBox1->Name = "ComboBox1";
      this->ComboBox1->Size = System::Drawing::Size( 100, 120 );
      this->ComboBox1->DropDownWidth = 250;
      this->ComboBox1->TabIndex = 0;
      this->ComboBox1->DropDownStyle = ComboBoxStyle::DropDown;
      animals = gcnew array<String^>{"Elephant","c r o c o d i l e","lion"};
      ComboBox1->DataSource = animals;
      this->Controls->Add( this->ComboBox1 );
      
      // Hook up the MeasureItem and DrawItem events
      this->ComboBox1->DrawItem +=
         gcnew DrawItemEventHandler( this, &Form1::ComboBox1_DrawItem );
      this->ComboBox1->MeasureItem +=
         gcnew MeasureItemEventHandler( this, &Form1::ComboBox1_MeasureItem );
   }

   // If you set the Draw property to DrawMode.OwnerDrawVariable, 
   // you must handle the MeasureItem event. This event handler 
   // will set the height and width of each item before it is drawn. 
private:
   void ComboBox1_MeasureItem( Object^ sender,
      System::Windows::Forms::MeasureItemEventArgs^ e )
   {
      switch ( e->Index )
      {
         case 0:
            e->ItemHeight = 45;
            break;
         case 1:
            e->ItemHeight = 20;
            break;
         case 2:
            e->ItemHeight = 35;
            break;
      }
      e->ItemWidth = 260;
   }

private:
   // You must handle the DrawItem event for owner-drawn combo boxes.  
   // This event handler changes the color, size and font of an 
   // item based on its position in the array.
   void ComboBox1_DrawItem( Object^ sender,
      System::Windows::Forms::DrawItemEventArgs^ e )
   {
      float size = 0;
      System::Drawing::Font^ myFont;
      FontFamily^ family = nullptr;

      System::Drawing::Color animalColor;
      switch ( e->Index )
      {
         case 0:
            size = 30;
            animalColor = System::Drawing::Color::Gray;
            family = FontFamily::GenericSansSerif;
            break;
         case 1:
            size = 10;
            animalColor = System::Drawing::Color::LawnGreen;
            family = FontFamily::GenericMonospace;
            break;
         case 2:
            size = 15;
            animalColor = System::Drawing::Color::Tan;
            family = FontFamily::GenericSansSerif;
            break;
      }

      // Draw the background of the item.
      e->DrawBackground();
      
      // Create a square filled with the animals color. Vary the size
      // of the rectangle based on the length of the animals name.
      Rectangle rectangle = Rectangle( 2, e->Bounds.Top + 2,
         e->Bounds.Height, e->Bounds.Height - 4 );
      e->Graphics->FillRectangle( gcnew SolidBrush( animalColor ), rectangle );
      
      // Draw each string in the array, using a different size, color,
      // and font for each item.
      myFont = gcnew System::Drawing::Font( family, size, FontStyle::Bold );
      e->Graphics->DrawString( animals[ e->Index ], myFont,
         System::Drawing::Brushes::Black, RectangleF(
            e->Bounds.X + rectangle.Width, e->Bounds.Y,
            e->Bounds.Width, e->Bounds.Height) );
      
      // Draw the focus rectangle if the mouse hovers over an item.
      e->DrawFocusRectangle();
   }

internal System.Windows.Forms.ComboBox ComboBox1;
private string[] animals;
 
// This method initializes the owner-drawn combo box.
// The drop-down width is set much wider than the size of the combo box
// to accomodate the large items in the list.  The drop-down style is set to 
// ComboBox.DropDown, which requires the user to click on the arrow to 
// see the list.
private void InitializeComboBox()
{
	this.ComboBox1 = new ComboBox();
	this.ComboBox1.DrawMode = 
		System.Windows.Forms.DrawMode.OwnerDrawVariable;
	this.ComboBox1.Location = new System.Drawing.Point(10, 20);
	this.ComboBox1.Name = "ComboBox1";
	this.ComboBox1.Size = new System.Drawing.Size(100, 120);
	this.ComboBox1.DropDownWidth = 250;
	this.ComboBox1.TabIndex = 0;
	this.ComboBox1.DropDownStyle = ComboBoxStyle.DropDown;
	animals = new string[]{"Elephant", "c r o c o d i l e", "lion"};
	ComboBox1.DataSource = animals;
	this.Controls.Add(this.ComboBox1);

	// Hook up the MeasureItem and DrawItem events
	this.ComboBox1.DrawItem += 
		new DrawItemEventHandler(ComboBox1_DrawItem);
	this.ComboBox1.MeasureItem += 
		new MeasureItemEventHandler(ComboBox1_MeasureItem);
}

// If you set the Draw property to DrawMode.OwnerDrawVariable, 
// you must handle the MeasureItem event. This event handler 
// will set the height and width of each item before it is drawn. 
private void ComboBox1_MeasureItem(object sender, 
	System.Windows.Forms.MeasureItemEventArgs e)
{

	switch(e.Index)
	{
		case 0:
			e.ItemHeight = 45;
			break;
		case 1:
			e.ItemHeight = 20;
			break;
		case 2:
			e.ItemHeight = 35;
			break;
	}
	e.ItemWidth = 260;

}

// You must handle the DrawItem event for owner-drawn combo boxes.  
// This event handler changes the color, size and font of an 
// item based on its position in the array.
private void ComboBox1_DrawItem(object sender, 
	System.Windows.Forms.DrawItemEventArgs e)
{

	float size = 0;
	System.Drawing.Font myFont;
	FontFamily family = null;

	System.Drawing.Color animalColor = new System.Drawing.Color();
	switch(e.Index)
	{
		case 0:
			size = 30;
			animalColor = System.Drawing.Color.Gray;
			family = FontFamily.GenericSansSerif;
			break;
		case 1:
			size = 10;
			animalColor = System.Drawing.Color.LawnGreen;
			family = FontFamily.GenericMonospace;
			break;
		case 2:
			size = 15;
			animalColor = System.Drawing.Color.Tan;
			family = FontFamily.GenericSansSerif;
			break;
	}

	// Draw the background of the item.
	e.DrawBackground();

	// Create a square filled with the animals color. Vary the size
	// of the rectangle based on the length of the animals name.
	Rectangle rectangle = new Rectangle(2, e.Bounds.Top+2, 
			e.Bounds.Height, e.Bounds.Height-4);
	e.Graphics.FillRectangle(new SolidBrush(animalColor), rectangle);

	// Draw each string in the array, using a different size, color,
	// and font for each item.
	myFont = new Font(family, size, FontStyle.Bold);
	e.Graphics.DrawString(animals[e.Index], myFont, System.Drawing.Brushes.Black, new RectangleF(e.Bounds.X+rectangle.Width, e.Bounds.Y, e.Bounds.Width, e.Bounds.Height));

	// Draw the focus rectangle if the mouse hovers over an item.
	e.DrawFocusRectangle();
}


Friend WithEvents ComboBox1 As System.Windows.Forms.ComboBox
Private animals() As String

' This method initializes the owner-drawn combo box.
' The drop-down width is set much wider than the size of the combo box
' to accomodate the large items in the list.  The drop-down style is set to 
' ComboBox.DropDown, which requires the user to click on the arrow to 
' see the list.
Private Sub InitializeComboBox()
    Me.ComboBox1 = New ComboBox
    Me.ComboBox1.DrawMode = System.Windows.Forms.DrawMode.OwnerDrawVariable
    Me.ComboBox1.Location = New System.Drawing.Point(10, 20)
    Me.ComboBox1.Name = "ComboBox1"
    Me.ComboBox1.Size = New System.Drawing.Size(100, 120)
    Me.ComboBox1.DropDownWidth = 250
    Me.ComboBox1.TabIndex = 0
    Me.ComboBox1.DropDownStyle = ComboBoxStyle.DropDown
    animals = New String() {"Elephant", "c r o c o d i l e", "lion"}
    ComboBox1.DataSource = animals
    Me.Controls.Add(Me.ComboBox1)
End Sub

' If you set the Draw property to DrawMode.OwnerDrawVariable, 
' you must handle the MeasureItem event. This event handler 
' will set the height and width of each item before it is drawn. 
 Private Sub ComboBox1_MeasureItem(ByVal sender As Object, _
    ByVal e As System.Windows.Forms.MeasureItemEventArgs) _
        Handles ComboBox1.MeasureItem

    Select Case e.Index
        Case 0
            e.ItemHeight = 45
        Case 1
            e.ItemHeight = 20
        Case 2
            e.ItemHeight = 35
    End Select
    e.ItemWidth = 260

End Sub

' You must handle the DrawItem event for owner-drawn combo boxes.  
' This event handler changes the color, size and font of an 
' item based on its position in the array.
Private Sub ComboBox1_DrawItem(ByVal sender As Object,  _ 
    ByVal e As System.Windows.Forms.DrawItemEventArgs) _
    Handles ComboBox1.DrawItem

    Dim size As Single
    Dim myFont As System.Drawing.Font
    Dim family As FontFamily

    Dim animalColor As New System.Drawing.Color
    Select Case e.Index
        Case 0
            size = 30
            animalColor = System.Drawing.Color.Gray
            family = FontFamily.GenericSansSerif
        Case 1
            size = 10
            animalColor = System.Drawing.Color.LawnGreen
            family = FontFamily.GenericMonospace
        Case 2
            size = 15
            animalColor = System.Drawing.Color.Tan
            family = FontFamily.GenericSansSerif
    End Select

    ' Draw the background of the item.
    e.DrawBackground()

    ' Create a square filled with the animals color. Vary the size
    ' of the rectangle based on the length of the animals name.
    Dim rectangle As Rectangle = New Rectangle(2, e.Bounds.Top + 2, _
        e.Bounds.Height, e.Bounds.Height - 4)
    e.Graphics.FillRectangle(New SolidBrush(animalColor), rectangle)

    ' Draw each string in the array, using a different size, color,
    ' and font for each item.
    myFont = New Font(family, size, FontStyle.Bold)
    e.Graphics.DrawString(animals(e.Index), myFont, System.Drawing.Brushes.Black, _
        New RectangleF(e.Bounds.X + rectangle.Width, e.Bounds.Y, _ 
        e.Bounds.Width, e.Bounds.Height))

    ' Draw the focus rectangle if the mouse hovers over an item.
    e.DrawFocusRectangle()
End Sub

注釈

プロパティDropDownStyleは、リストを常に表示するかどうか、またはリストをドロップダウンに表示するかどうかを指定します。The DropDownStyle property specifies whether the list is always displayed or whether the list is displayed in a drop-down. プロパティDropDownStyleは、テキスト部分を編集できるかどうかも指定します。The DropDownStyle property also specifies whether the text portion can be edited. 使用ComboBoxStyle可能な設定とその効果については、「」を参照してください。See ComboBoxStyle for the available settings and their effects. 常に一覧を表示し、新しい値の入力を禁止する設定はありません。There is no setting to always display the list and disallow entering a new value. 新しい値を追加できない一覧を表示するには、 ListBoxコントロールを使用します。To display a list to which no new values can be added, use a ListBox control.

適用対象

こちらもご覧ください