public event InteractiveActionEnterEventHandler InteractiveActionEnter

Public Event InteractiveActionEnter As InteractiveActionEnterEventHandler

void reportViewer1_InteractiveActionEnter(object sender, Telerik.ReportViewer.Common.InteractiveActionEventArgs args)
{
    var strB = new System.Text.StringBuilder();
    strB.AppendLine("You have just entered an action area.");
    strB.AppendLine("Action type: " + args.Action.GetType().Name);
    strB.AppendLine("ReportItem name: " + args.Action.ReportItemName);
    strB.AppendLine(string.Format("Mouse cursor position: {0}; Item bounds: {1}", args.CursorPos, args.Bounds));

    Console.Out.WriteLine(strB.ToString());
}

' Handles the InteractiveActionEnter event
' Do not forget to add the WithEvents clause on ReportViewer1 instantiation if needed.
Private Sub reportViewer1_InteractiveActionEnter(sender As Object, args As Telerik.ReportViewer.Common.InteractiveActionEventArgs) Handles ReportViewer1.InteractiveActionEnter

    Dim strB = New System.Text.StringBuilder()
    strB.AppendLine("You have just entered an action area.")
    strB.AppendLine("Action type: " + args.Action.[GetType]().Name)
    strB.AppendLine("ReportItem name: " + args.Action.ReportItemName)
    strB.AppendLine(String.Format("Mouse cursor position: {0}; Item bounds: {1}", args.CursorPos, args.Bounds))

    Console.Out.WriteLine(strB.ToString())
End Sub