dotConnect for MySQL Documentation
Devart.Common Namespace / DbMonitor Class / TraceEvent Event
Example

In This Topic
    TraceEvent Event
    In This Topic
    Occurs when DbMonitor object signals about some database activity.
    Syntax
    'Declaration
     
    Public Event TraceEvent As MonitorEventHandler
    public event MonitorEventHandler TraceEvent
    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.  
    The time between the start and the end of the 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.
    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)
    {
      MySqlConnection myConn = new MySqlConnection(
          "User Id=root;Host=localhost;Database=Test;");
      MySqlMonitor myMonitor = new MySqlMonitor();
      myMonitor.TraceEvent += new MonitorEventHandler(OnEvent);
      myMonitor.IsActive = true;
      MySqlCommand myCommand = new MySqlCommand("select count(*) from Dept",myConn);
      myConn.Open();
      Console.WriteLine(myCommand.ExecuteScalar());
      myConn.Close();
      myMonitor.TraceEvent -= new MonitorEventHandler(OnEvent);
      Console.ReadLine();
    }
    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
    
    <MTAThread()> _
    Sub Main()
      Dim myConn As MySqlConnection = New MySqlConnection( _
          "User Id=root;Host=localhost;Database=Test;")
      Dim myMonitor As MySqlMonitor = New MySqlMonitor
      AddHandler myMonitor.TraceEvent, AddressOf OnEvent
      myMonitor.IsActive = True
      Dim myCommand As MySqlCommand = New MySqlCommand("select count(*) from Dept", myConn)
      myConn.Open()
      Console.WriteLine(myCommand.ExecuteScalar())
      myConn.Close()
      RemoveHandler myMonitor.TraceEvent, AddressOf OnEvent
      Console.ReadLine()
    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