EventSource.WriteEventWithRelatedActivityIdCore Method (Int32, Guid*, Int32, EventSource.EventData*)

.NET Framework (current version)

The .NET API Reference documentation has a new home. Visit the .NET API Browser on to see the new experience.

[Supported in the .NET Framework 4.5.1 and later versions]

Writes an event that indicates that the current activity is related to another activity.

This API is not CLS-compliant.

Namespace:   System.Diagnostics.Tracing
Assembly:  mscorlib (in mscorlib.dll)

Visual Basic does not support APIs that consume or return unsafe types.


Type: System.Int32

An identifier that uniquely identifies this event within the EventSource.

Type: System.Guid*

A pointer to the GUID of the related activity ID.

Type: System.Int32

The number of items in the data field.

Type: System.Diagnostics.Tracing.EventSource.EventData*

A pointer to the first item in the event data field.

WriteEventWithRelatedActivityIdCore is similar to the WriteEventWithRelatedActivityId method but offers better performance, bevcause it does not have to unbox the childActivityID and data arguments.

Your ETW event method calling this function must follow these guidelines:

  1. Specify the first parameter as a Guid named relatedActivityId.

  2. Specify either Send or Receive as the EventAttribute.Opcode property.

  3. Call WriteEventWithRelatedActivityIdCore passing in the event ID, followed by the related ID GUID, followed by all the parameters the event method is passed, in the same order.

The following C# code example shows how to define a method overload that calls WriteEventWithRelatedActivityIdCore.

<EventSource(Name:="Litware-ProductName-ComponentName")> _
Public NotInheritable Class LitwareComponentNameEventSource
    Inherits EventSource
    <[Event](1, Task:=Tasks.Request, Opcode:=EventOpcode.Send)> _
    Public Sub RequestStart(relatedActivityId As Guid, reqId As Integer, url As String)
        WriteEventWithRelatedActivityIdCore(1, relatedActivityId, reqId, url)
    End Sub

End Class

#Region "Keywords / Task / Opcodes"
    Public NotInheritable Class Tasks
        Private Sub New()
        End Sub
        Public Const Request As EventTask = DirectCast(&H1, EventTask)
    End Class
#End Region

Universal Windows Platform
Available since 8.1
.NET Framework
Available since 4.5.1
Portable Class Library
Supported in: portable .NET platforms
Windows Phone
Available since 8.1
Return to top