本文整理汇总了C#中ObservableList.FirstOrDefault方法的典型用法代码示例。如果您正苦于以下问题：C# ObservableList.FirstOrDefault方法的具体用法？C# ObservableList.FirstOrDefault怎么用？C# ObservableList.FirstOrDefault使用的例子？那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类ObservableList的用法示例。
在下文中一共展示了ObservableList.FirstOrDefault方法的1个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的C#代码示例。
示例1: LocationsTreeViewModel
public LocationsTreeViewModel(ObservableCollection<Location> locations)
{
Locations = new ObservableList<LocationNode>();
foreach (var location in locations) Locations.Add(new LocationNode(location));
locations.CollectionChanged += (s, e) =>
{
switch (e.Action)
{
case NotifyCollectionChangedAction.Add:
foreach (Location location in e.NewItems) Locations.Add(new LocationNode(location));
break;
case NotifyCollectionChangedAction.Remove:
foreach (Location location in e.OldItems)
{
var item = Locations.FirstOrDefault(l => l.Location.Guid == location.Guid);
if (item != null) Locations.Remove(item);
}
break;
case NotifyCollectionChangedAction.Replace:
foreach (Location location in e.OldItems)
{
var item = Locations.FirstOrDefault(l => l.Location.Guid == location.Guid);
if (item != null) Locations.Remove(item);
}
foreach (Location location in e.NewItems) Locations.Add(new LocationNode(location));
break;
case NotifyCollectionChangedAction.Reset:
Locations.Clear();
foreach (Location location in e.NewItems) Locations.Add(new LocationNode(location));
break;
}
};
LocationsTreeViewSource = new CollectionViewSource { Source = Locations };
LocationsTreeViewSource.SortDescriptions.Add(new SortDescription("Location.Name", ListSortDirection.Ascending));
}