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DataSourceView.CanUpdate Property

  • Reference

Definition

Namespace:
System.Web.UI
Assembly:
System.Web.dll

Gets a value indicating whether the DataSourceView object associated with the current DataSourceControl object supports the ExecuteUpdate(IDictionary, IDictionary, IDictionary) operation.

public:
 virtual property bool CanUpdate { bool get(); };
public virtual bool CanUpdate { get; }
member this.CanUpdate : bool
Public Overridable ReadOnly Property CanUpdate As Boolean

Property Value

Boolean

true if the operation is supported; otherwise, false. The default implementation returns false.

Examples

The following code example demonstrates how to override the CanUpdate property and the ExecuteUpdate method in a class that extends the DataSourceView class. This code example is part of a larger example provided for the DataSourceView class.

// The CsvDataSourceView does not currently
// permit update operations. You can modify or
// extend this sample to do so.
public override bool CanUpdate {
    get {
        return false;
    }
}
protected override int ExecuteUpdate(IDictionary keys, IDictionary values, IDictionary oldValues)
{
    throw new NotSupportedException();
}

   ' The CsvDataSourceView does not currently
   ' permit update operations. You can modify or
   ' extend this sample to do so.
   Public Overrides ReadOnly Property CanUpdate() As Boolean
      Get
         Return False
      End Get
   End Property

   Protected Overrides Function ExecuteUpdate(keys As IDictionary, _
                                              values As IDictionary, _
                                              oldValues As IDictionary) As Integer
      Throw New NotSupportedException()
   End Function 'ExecuteUpdate

End Class

Remarks

The CanUpdate property reflects not only a capability of the data source control, but also whether it is currently appropriate to perform an operation. For example, even though a data-bound control supports the ExecuteUpdate operation, if a required update command or some other data is not set, the CanUpdate property returns false, as an update operation would fail.

Applies to

See also