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CurrencyManager.List Property

  • Reference

Definition

Namespace:
System.Windows.Forms
Assembly:
System.Windows.Forms.dll

Gets the list for this CurrencyManager.

public:
 property System::Collections::IList ^ List { System::Collections::IList ^ get(); };
public System.Collections.IList List { get; }
member this.List : System.Collections.IList
Public ReadOnly Property List As IList

Property Value

IList

An IList that contains the list.

Examples

The following code example allows users to edit a set of records, but not add any new ones. In the Navigate event of a DataGrid control, the IList returned by the List property is cast to a DataView variable. The AllowNew property of the DataView is set to false.

private:
   void Grid_Navigate( Object^ /*sender*/, NavigateEventArgs^ e )
   {
      if ( e->Forward )
      {
         DataSet^ ds = dynamic_cast<DataSet^>(grid->DataSource);
         CurrencyManager^ cm = dynamic_cast<CurrencyManager^>(BindingContext[ds, "Customers::CustOrders"]);
         
         // Cast the IList* to a DataView to set the AllowNew property.
         DataView^ dv = dynamic_cast<DataView^>(cm->List);
         dv->AllowNew = false;
      }
   }

private void Grid_Navigate(object sender, NavigateEventArgs e){
   if (e.Forward ){
      DataSet ds = (DataSet) grid.DataSource;
      CurrencyManager cm  = 
      (CurrencyManager)BindingContext[ds,"Customers.CustOrders"];
      // Cast the IList to a DataView to set the AllowNew property.
      DataView dv  = (DataView) cm.List;
      dv.AllowNew = false;
   }
}

Private Sub Grid_Navigate(sender As Object, e As NavigateEventArgs)
   If e.Forward Then
      Dim ds As DataSet = CType(grid.DataSource, DataSet)
      Dim cm As CurrencyManager = _
      CType(BindingContext(ds,"Customers.CustOrders"), CurrencyManager)
      ' Cast the IList to a DataView to set the AllowNew property.
      Dim dv As DataView = CType(cm.List, DataView)
      dv.AllowNew = false
   End If
End Sub

Remarks

The object returned by the List property can be cast to any type that implements the IList interface. This will be commonly used when you know the type of the underlying list. For example, if you are data-bound to a DataSet, the underlying list is a DataView (which implements IList). Other classes that implement the interface (this is not a complete list) include Array, ArrayList, and CollectionBase.

How you use the List property depends on the class that implements the IList interface. For example, you can use the List property to determine the name of the list. If the data source implements the ITypedList interface, you can use the GetListName method to return the name of the current table. This is shown in the C# code below:

private void PrintCurrentListName(DataGrid myDataGrid){   
   CurrencyManager myCM = (CurrencyManager)   
   BindingContext[myDataGrid.DataSource, myDataGrid.DataMember];   
   IList myList = myCM.List;   
   ITypedList thisList = (ITypedList) myList;   
   Console.WriteLine(thisList.GetListName(null));   
}

Applies to

See also