我有一个 WPF 应用程序,其中 UI 有一个列表框。列表框绑定(bind)了 ObservableCollection。日志类实现 INotifyPropertyChanged。
该列表将显示应用程序的连续日志记录。只要应用程序正在运行。 ObservableCollection 大小不断增长。一段时间后,我得到了内存不足异常。我想在列表控件中显示最新的 1000 个条目。对此的任何建议都会有很大帮助!
XAML:
<DataGrid AutoGenerateColumns="False" SelectedValue="{Binding SelectedLog}" SelectionUnit="FullRow" SelectionMode="Single" Name="dataGridLogs"
ItemsSource="{Binding Path=LogList}" CanUserReorderColumns="True" CanUserResizeRows="True" CanUserDeleteRows="False" IsReadOnly="True"
CanUserAddRows="False" EnableColumnVirtualization="True" EnableRowVirtualization="True" SelectionChanged="grid_SelectionChanged">
<DataGrid.Columns>
<DataGridTextColumn Header="Time Stamp" Binding="{Binding StrTimeStamp, Mode=OneWay}" Width="Auto"/>
<DataGridTextColumn Header="Action" Binding="{Binding Action, Mode=OneWay}" Width="Auto"/>
</DataGrid>
View 模型:
public ObservableCollection<LogData> LogList
{
get
{
if (logList == null)
{
logList = new ObservableCollection<LogData>();
}
return logList;
}
set
{
logList = value;
OnPropertyChanged("LogList");
}
}
型号:
public class LogData : INotifyPropertyChanged
{
public LogData()
{
}
private String timestamp = string.Empty;
public String StrTimestamp
{
get
{
if (timestamp == null)
return string.Empty;
return timestamp ;
}
set
{
timestamp = value;
}
}
public string Action
{
get;set;
}
最佳答案
您可以创建自己的大小受限的可观察集合类。像这样的事情应该让你开始:
public class LimitedSizeObservableCollection<T> : INotifyCollectionChanged
{
private ObservableCollection<T> _collection;
private bool _ignoreChange;
public LimitedSizeObservableCollection(int capacity)
{
Capacity = capacity;
_ignoreChange = false;
_collection = new ObservableCollection<T>();
_collection.CollectionChanged += _collection_CollectionChanged;
}
public event NotifyCollectionChangedEventHandler CollectionChanged;
public int Capacity {get;}
public void Add(T item)
{
if(_collection.Count = Capacity)
{
_ignoreChange = true;
_collection.RemoveAt(0);
_ignoreChange = false;
}
_collection.Add(item);
}
private void _collection_CollectionChanged(object sender, NotifyCollectionChangedEventArgs e)
{
if(!_ignoreChange)
{
CollectionChanged?.Invoke(this, e);
}
}
}
当然,您可能需要公开更多的方法,但我希望这足以让您理解。
关于c# - .net c# 限制 observablecollection 中的条目数,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/50121550/