FrameworkElement.ActualWidth Properti

Definisi

Ruang nama:

System.Windows

Rakitan:

PresentationFramework.dll

Mendapatkan lebar yang dirender dari elemen ini.

public:
 property double ActualWidth { double get(); };

public double ActualWidth { get; }

member this.ActualWidth : double

Public ReadOnly Property ActualWidth As Double

Nilai Properti

Double

Lebar elemen, sebagai nilai dalam unit independen perangkat (1/96 inci per unit). Nilai defaultnya adalah 0 (nol).

Contoh

Contoh berikut menampilkan berbagai properti lebar.

private void changeWidth(object sender, SelectionChangedEventArgs args)
{
    ListBoxItem li = ((sender as ListBox).SelectedItem as ListBoxItem);
    Double sz1 = Double.Parse(li.Content.ToString());
    rect1.Width = sz1;
    rect1.UpdateLayout();
    txt1.Text = "ActualWidth is set to " + rect1.ActualWidth;
    txt2.Text = "Width is set to " + rect1.Width;
    txt3.Text = "MinWidth is set to " + rect1.MinWidth;
    txt4.Text = "MaxWidth is set to " + rect1.MaxWidth;
}
private void changeMinWidth(object sender, SelectionChangedEventArgs args)
{
    ListBoxItem li = ((sender as ListBox).SelectedItem as ListBoxItem);
    Double sz1 = Double.Parse(li.Content.ToString());
    rect1.MinWidth = sz1;
    rect1.UpdateLayout();
    txt1.Text = "ActualWidth is set to " + rect1.ActualWidth;
    txt2.Text = "Width is set to " + rect1.Width;
    txt3.Text = "MinWidth is set to " + rect1.MinWidth;
    txt4.Text = "MaxWidth is set to " + rect1.MaxWidth;
}
private void changeMaxWidth(object sender, SelectionChangedEventArgs args)
{
    ListBoxItem li = ((sender as ListBox).SelectedItem as ListBoxItem);
    Double sz1 = Double.Parse(li.Content.ToString());
    rect1.MaxWidth = sz1;
    rect1.UpdateLayout();
    txt1.Text = "ActualWidth is set to " + rect1.ActualWidth;
    txt2.Text = "Width is set to " + rect1.Width;
    txt3.Text = "MinWidth is set to " + rect1.MinWidth;
    txt4.Text = "MaxWidth is set to " + rect1.MaxWidth;
}

Private Sub changeWidth(ByVal sender As Object, ByVal args As SelectionChangedEventArgs)
    Dim li As ListBoxItem = CType(CType(sender, ListBox).SelectedItem, ListBoxItem)
    Dim sz1 As Double = Double.Parse(li.Content.ToString())
    rect1.Width = sz1
    rect1.UpdateLayout()
    txt1.Text = "ActualWidth is set to " + rect1.ActualWidth.ToString
    txt2.Text = "Width is set to " + rect1.Width.ToString
    txt3.Text = "MinWidth is set to " + rect1.MinWidth.ToString
    txt4.Text = "MaxWidth is set to " + rect1.MaxWidth.ToString
End Sub
Private Sub changeMinWidth(ByVal sender As Object, ByVal args As SelectionChangedEventArgs)

    Dim li As ListBoxItem = CType(CType(sender, ListBox).SelectedItem, ListBoxItem)
    Dim sz1 As Double = Double.Parse(li.Content.ToString())
    rect1.MinWidth = sz1
    rect1.UpdateLayout()
    txt1.Text = "ActualWidth is set to " + rect1.ActualWidth.ToString
    txt2.Text = "Width is set to " + rect1.Width.ToString
    txt3.Text = "MinWidth is set to " + rect1.MinWidth.ToString
    txt4.Text = "MaxWidth is set to " + rect1.MaxWidth.ToString
End Sub
Private Sub changeMaxWidth(ByVal sender As Object, ByVal args As SelectionChangedEventArgs)

    Dim li As ListBoxItem = CType(CType(sender, ListBox).SelectedItem, ListBoxItem)
    Dim sz1 As Double = Double.Parse(li.Content.ToString())
    rect1.MaxWidth = sz1
    rect1.UpdateLayout()
    txt1.Text = "ActualWidth is set to " + rect1.ActualWidth.ToString
    txt2.Text = "Width is set to " + rect1.Width.ToString
    txt3.Text = "MinWidth is set to " + rect1.MinWidth.ToString
    txt4.Text = "MaxWidth is set to " + rect1.MaxWidth.ToString
End Sub

Keterangan

Properti ini adalah nilai terhitung berdasarkan input lebar lainnya, dan sistem tata letak. Nilai diatur oleh sistem tata letak itu sendiri, berdasarkan pass penyajian aktual, dan karenanya mungkin sedikit tertinggal di belakang nilai properti yang ditetapkan seperti Width yang merupakan dasar dari perubahan input.

Karena ActualWidth adalah nilai yang dihitung, Anda harus menyadari bahwa mungkin ada berbagai perubahan yang dilaporkan secara bertahap akibat dari berbagai operasi oleh sistem tata letak. Sistem tata letak mungkin menghitung ruang pengukuran yang diperlukan untuk elemen anak, batasan oleh elemen induk, dan sebagainya.

Meskipun Anda tidak dapat mengatur properti ini dari XAML, Anda dapat mendasarkan Trigger nilainya dalam gaya.

Informasi Properti Dependensi

Barang	Nilai
Bidang pengidentifikasi	ActualWidthProperty
Properti metadata diatur ke true	Tidak