未将对象引用设置到对象的实例。

在 MT4APIGD.Zzh.update_Xuanfuitems() 位置 D:\datas\zcw\Csharpe\MT4API-HF-CHARt-quanping-web-xuanfu\Zzh.xaml.cs:行号 100
在 MT4APIGD.Zzh.TreevList_SelectedItemChanged(Object sender, RoutedPropertyChangedEventArgs`1 e) 位置 D:\datas\zcw\Csharpe\MT4API-HF-CHARt-quanping-web-xuanfu\Zzh.xaml.cs:行号 390
在 System.Windows.RoutedPropertyChangedEventArgs`1.InvokeEventHandler(Delegate genericHandler, Object genericTarget)
在 System.Windows.RoutedEventArgs.InvokeHandler(Delegate handler, Object target)
在 System.Windows.RoutedEventHandlerInfo.InvokeHandler(Object target, RoutedEventArgs routedEventArgs)
在 System.Windows.EventRoute.InvokeHandlersImpl(Object source, RoutedEventArgs args, Boolean reRaised)
在 System.Windows.UIElement.RaiseEventImpl(DependencyObject sender, RoutedEventArgs args)
在 System.Windows.UIElement.RaiseEvent(RoutedEventArgs e)
在 System.Windows.Controls.TreeView.OnSelectedItemChanged(RoutedPropertyChangedEventArgs`1 e)
在 System.Windows.Controls.TreeView.ChangeSelection(Object data, TreeViewItem container, Boolean selected)
在 System.Windows.Controls.TreeViewItem.Select(Boolean selected)
在 System.Windows.Controls.TreeViewItem.OnGotFocus(RoutedEventArgs e)
在 System.Windows.UIElement.IsFocused_Changed(DependencyObject d, DependencyPropertyChangedEventArgs e)
在 System.Windows.DependencyObject.OnPropertyChanged(DependencyPropertyChangedEventArgs e)
在 System.Windows.FrameworkElement.OnPropertyChanged(DependencyPropertyChangedEventArgs e)
在 System.Windows.DependencyObject.NotifyPropertyChange(DependencyPropertyChangedEventArgs args)
在 System.Windows.DependencyObject.UpdateEffectiveValue(EntryIndex entryIndex, DependencyProperty dp, PropertyMetadata metadata, EffectiveValueEntry oldEntry, EffectiveValueEntry