LinqConnect Documentation
Devart.Data.Linq.Monitoring Namespace / DbMonitor Class / TraceEvent Event
Example

TraceEvent Event
Occurs when DbMonitor object signals about some database activity.
Syntax
'Declaration
 
Public Event TraceEvent As MonitorEventHandler
 
Event Data

The event handler receives an argument of type MonitorEventArgs containing data related to this event. The following MonitorEventArgs properties provide information specific to this event.

PropertyDescription
Gets the call stack of the monitor event.  
Gets the description of a DbMonitor event.  
Gets DbMonitor event type.  
Gets the additional information for a DbMonitor event.  
Determines whether TraceEvent event occurs before or after the operation takes place.  
Example
The following sample shows how to enable and disable monitoring of database activity in your application.
using Devart.Data.Linq.Monitoring;

...

static void OnEvent(object sender, MonitorEventArgs e)
{
  if (e.TracePoint==MonitorTracePoint.BeforeEvent)
  {
    Console.WriteLine("Description: " + e.Description);
    Console.WriteLine(" Extra info: " + e.ExtraInfo);
  }
}

[MTAThread]
static void Main(string[] args)
{
LinqMonitor linqMonitor=new LinqMonitor();
linqMonitor.IsActive = true;
CrmDemoContext.CrmDemoDataContext db = new CrmDemoContext.CrmDemoDataContext();
linqMonitor.TraceEvent += new Devart.Data.Linq.Monitoring.MonitorEventHandler(OnEvent);
var query = from it in db.Companies
    select it;
linqMonitor.TraceEvent -= OnEvent;
}
Imports Devart.Data.Linq.Monitoring

...

Private Shared Sub OnEvent(ByVal sender As Object, ByVal e As MonitorEventArgs)
  If (e.TracePoint = MonitorTracePoint.BeforeEvent) Then
    Console.WriteLine(("Description: " & e.Description))
    Console.WriteLine((" Extra info: " & e.ExtraInfo))
  End If
End Sub

Private Shared Sub Main(ByVal args As String())
   Dim linqMonitor As New LinqMonitor
   linqMonitor.IsActive = True
   Dim db As New CrmDemoContext.CrmDemoDataContext
   AddHandler linqMonitor.TraceEvent, New MonitorEventHandler(AddressOf Program.OnEvent)
   Dim comp As CrmDemoContext.Company
   For Each comp In query
       Console.WriteLine(comp.CompanyName)
   Next
   RemoveHandler linqMonitor.TraceEvent, New MonitorEventHandler(AddressOf Program.OnEvent)
End Sub
Requirements

Target Platforms: Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

See Also