示例
下面的示例演示如何创建和使用 GridLengthConverter 的实例。 此示例定义了一个名为 changeCol 的自定义方法，该方法将 ListBoxItem 传递给 GridLengthConverter，它将 ListBoxItem 的Content转换为 GridLength 的实例。 转换后的值然后作为 ColumnDefinition 元素的 Width 属性值进行回传。
此示例还定义了名为 changeColVal 的第二个自定义方法。 此自定义方法将Slider的Value转换为String，然后将该值作为元素的 Width 回传给 ColumnDefinition。
请注意，ListBoxItem 的内容在单独的Extensible Application Markup Language (XAML) 文件中定义。
Private Sub changeColVal(ByVal sender As Object, ByVal args As RoutedPropertyChangedEventArgs(Of Double))
txt1.Text = "Current Grid Column is " + hs1.Value.ToString()
End Sub
Private Sub changeCol(ByVal sender As Object, ByVal args As SelectionChangedEventArgs)
Dim li1 As ListBoxItem = CType(CType(sender, ListBox).SelectedItem, ListBoxItem)
Dim myGridLengthConverter As System.Windows.GridLengthConverter = New System.Windows.GridLengthConverter()
If (hs1.Value = 0) Then
Dim gl1 As GridLength = CType(myGridLengthConverter.ConvertFromString(li1.Content.ToString()), GridLength)
col1.Width = gl1
ElseIf (hs1.Value = 1) Then
Dim gl2 As GridLength = CType(myGridLengthConverter.ConvertFromString(li1.Content.ToString()), GridLength)
col2.Width = gl2
ElseIf (hs1.Value = 2) Then
Dim gl3 As GridLength = CType(myGridLengthConverter.ConvertFromString(li1.Content.ToString()), GridLength)
col3.Width = gl3
End If
End Sub
private void changeColVal(object sender, RoutedEventArgs e)
{
txt1.Text = "Current Grid Column is " + hs1.Value.ToString();
}
private void changeCol(object sender, SelectionChangedEventArgs args)
{
ListBoxItem li = ((sender as ListBox).SelectedItem as ListBoxItem);
GridLengthConverter myGridLengthConverter = new GridLengthConverter();
if (hs1.Value == 0)
{
GridLength gl1 = (GridLength)myGridLengthConverter.ConvertFromString(li.Content.ToString());
col1.Width = gl1;
}
else if (hs1.Value == 1)
{
GridLength gl2 = (GridLength)myGridLengthConverter.ConvertFromString(li.Content.ToString());
col2.Width = gl2;
}
else if (hs1.Value == 2)
{
GridLength gl3 = (GridLength)myGridLengthConverter.ConvertFromString(li.Content.ToString());
col3.Width = gl3;
}
}