WPF VisualTreeHelper.GetChildrenCount(MyMap) returns 1（边框）当 MyMap.Children.Count = 1237

Question

在我的 WPF BingMaps 应用程序中，我使用命令“MyMap.Children.Add(image);”

添加了 1237 个“System.Windows.Controls.Image”图像

当我想删除它们时，我尝试使用方法 below.Here 我得到 mychildren result = 1237 但 VisualTreeHelper.GetChildrenCount(MyMap) returns 1（边框类型）。这里有什么问题？谢谢

private void limpaaerop()
    {
        int mychildren = MyMap.Children.Count; // result = 1237
        for (int i = 0; i < VisualTreeHelper.GetChildrenCount(MyMap); i++)
        {
            Visual childVisual = (Visual)VisualTreeHelper.GetChild(MyMap, i);
            if (childVisual is System.Windows.Controls.Image)
            {
                MyMap.Children.Remove((UIElement)childVisual);
            }
        }
    }

Maingrid 内部 Xaml

  </UserControl.Resources>

<Grid x:Name="maingrid" Margin="0,0,0,0">
    <Grid.RowDefinitions>
      .....
    </Grid.RowDefinitions>
    <Grid.ColumnDefinitions>
        ....
   </Grid.ColumnDefinitions>
    <StackPanel x:Name="mapStack" Grid.Row="0" Grid.RowSpan="12" Grid.Column="0" Grid.ColumnSpan="9">
        <map:Map x:Name="MyMap"  Margin="0,0,0,0"  />
    </StackPanel>

Answer 1

您应该遍历 MyMap.Children 而不是 VisualTreeHelper.GetChildrenCount(MyMap):

private void limpaaerop()
{
    int mychildren = MyMap.Children.Count;
    for (int i = mychildren - 1; i >= 0; i--)
    {
        UIElement childVisual = MyMap.Children[i];
        if (childVisual is System.Windows.Controls.Image)
        {
            MyMap.Children.Remove(childVisual);
        }
    }
}

WPF VisualTreeHelper.GetChildrenCount(MyMap) returns 1（边框）当 MyMap.Children.Count = 1237

WPF VisualTreeHelper.GetChildrenCount(MyMap) returns 1 (Border) when MyMap.Children.Count = 1237

c#

wpf

bing-maps