MonitorEventHandler Delegate

In This Topic

Represents the method that will handle the TraceEvent event of the DbMonitor class.

Syntax

Visual Basic
C#

'Declaration
 
Public Delegate Sub MonitorEventHandler( _
   ByVal sender As Object, _
   ByVal e As MonitorEventArgs _
)

public delegate void MonitorEventHandler( 
   object sender,
   MonitorEventArgs e
)

Parameters

sender: The source of the event.
e: The MonitorEventArgs object that contains the event data.

Remarks

When you create a MonitorEventArgs delegate, you identify the method that will handle the event. To associate the event with your event handler, add an instance of the delegate to the event. The event handler is called whenever the event occurs, unless you remove the delegate. For more information about event handler delegates, see "Events and Delegates" in the .NET Framework SDK documentation.

Example

The following sample shows how to enable and disable monitoring of database activity in your application.

csharp

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;
}

Visual Basic

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

Reference

MonitorEventHandler Members
Devart.Data.Linq.Monitoring Namespace

Send Feedback