ComboBoxRenderer.IsSupported Properti

Definisi

Ruang nama:

System.Windows.Forms

Rakitan:

System.Windows.Forms.dll

Sumber:

ComboBoxRenderer.cs

Mendapatkan nilai yang menunjukkan apakah ComboBoxRenderer kelas dapat digunakan untuk menggambar kotak kombo dengan gaya visual.

public:
 static property bool IsSupported { bool get(); };

public static bool IsSupported { get; }

static member IsSupported : bool

Public Shared ReadOnly Property IsSupported As Boolean

Nilai Properti

Boolean

true jika pengguna telah mengaktifkan gaya visual dalam sistem operasi dan gaya visual diterapkan ke area klien jendela aplikasi; jika tidak, false.

Contoh

Contoh kode berikut menggunakan IsSupported properti untuk menentukan apakah akan menggunakan ComboBoxRenderer metode . Contoh kode ini adalah bagian dari contoh yang lebih besar yang disediakan untuk ComboBoxRenderer kelas .

      // Draw the combo box in the current state.
protected:
    virtual void OnPaint(PaintEventArgs^ e) override 
    {
        Control::OnPaint(e);

        if (!ComboBoxRenderer::IsSupported)
        {
            this->Parent->Text = "Visual Styles Disabled";
            return;
        }

        this->Parent->Text = "CustomComboBox Enabled";

        // Always draw the main text box and drop down arrow in their
        // current states
        ComboBoxRenderer::DrawTextBox(e->Graphics, topTextBoxRectangle,
            this->Text, this->Font, textBoxState);
        ComboBoxRenderer::DrawDropDownButton(e->Graphics, arrowRectangle,
            arrowState);

        // Only draw the bottom text box if the arrow has been clicked
        if (isActivated)
        {
            ComboBoxRenderer::DrawTextBox(e->Graphics,
                bottomTextBoxRectangle, bottomText, this->Font,
                textBoxState);
        }
    }

// Draw the combo box in the current state.
protected override void OnPaint(PaintEventArgs e)
{
    base.OnPaint(e);

    if (!ComboBoxRenderer.IsSupported)
    {
        this.Parent.Text = "Visual Styles Disabled";
        return;
    }

    this.Parent.Text = "CustomComboBox Enabled";

    // Always draw the main text box and drop down arrow in their 
    // current states
    ComboBoxRenderer.DrawTextBox(e.Graphics, topTextBoxRectangle,
        this.Text, this.Font, textBoxState);
    ComboBoxRenderer.DrawDropDownButton(e.Graphics, arrowRectangle,
        arrowState);

    // Only draw the bottom text box if the arrow has been clicked
    if (isActivated)
    {
        ComboBoxRenderer.DrawTextBox(e.Graphics,
            bottomTextBoxRectangle, bottomText, this.Font,
            textBoxState);
    }
}

' Draw the combo box in the current state.
Protected Overrides Sub OnPaint(ByVal e As PaintEventArgs)
    MyBase.OnPaint(e)

    If Not ComboBoxRenderer.IsSupported Then
        Me.Parent.Text = "Visual Styles	Disabled"
        Return
    End If

    Me.Parent.Text = "CustomComboBox Enabled"

    ' Always draw the main text box and drop down arrow in their 
    ' current states.
    ComboBoxRenderer.DrawTextBox(e.Graphics, topTextBoxRectangle, _
        Me.Text, Me.Font, textBoxState)
    ComboBoxRenderer.DrawDropDownButton(e.Graphics, arrowRectangle, _
        arrowState)

    ' Only draw the bottom text box if the arrow has been clicked.
    If isActivated Then
        ComboBoxRenderer.DrawTextBox(e.Graphics, _
            bottomTextBoxRectangle, bottomText, Me.Font, textBoxState)
    End If
End Sub

Keterangan

Jika properti ini adalah false, DrawTextBox metode atau DrawDropDownButton akan melempar .InvalidOperationException

Lihat juga

• VisualStyleState