INotifyPropertyChanged or INotifyCollectionChanged with DataTable?
Hi i am having some troube with DataTables. So What i need is to detect whenever开发者_运维技巧 i change any cell in the DataGrid of the DataTable that is binded.
How to do it? With INotifyPropertyChanged
or with INotifyCollectionChanged
?
Note: I am trying with INotifyPropertyChanged
but it only detects when i set some value in the DataTable, and never when i change any value of any cell in the DataGrid, i already have tried OneWay
and TwoWay
but nothing happens.
Thanks in advance!
The datagrid would be bound to a list of objects. If you want the grid to update when individual object properties change, than each contained object must implement the INotifyPropertyChanged
interface.
The INotifyCollectionChanged
is an interface that the collection should implement, and are for notifications of addition and removal events.
See the section "How to implement collections" on this page.
Here's a way to approach your problem:
- Create a new class that exposes the properties currently held in each
DataRow
. On this class implementINotifyPropertyChanged
. - Instead of a
DataTable
, use anObservableCollection<T>
or your new class.
ObservableCollection
already implements INotifyCollectionChanged
, so this saves you the effort of implementing it yourself.
if you set the itemssource of your datagrid to a datatable then wpf create a IBindingListView wich is bound to the datagrid.
what you can do now is edit,add and delete items to your datatable via datagrid. if you wanna know when a cell in your datatable is changed you can subscribe to DataTable.ColumnChanged event.
why do you want do know when a cell is changed?
The answer to the title of your question is : Neither. Actually you do not need to bind a DataTable to a DataGrid. You bind a DataView. "The ADO.NET DataView implements the IBindingList interface, which provides change notifications that the binding engine listens for."(Binding Sources Overview) One answer to your question is : You modify the datagrid cell with a TextBox (usually). Do this with a new textbox inheriting from TextBox and override the OnGotFocus and OnLostFocus methods of it.
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