SqlTriggerContext Class

SqlTriggerContext Class


Provides contextual information about the trigger that was fired.

Namespace:   Microsoft.SqlServer.Server
Assembly:  System.Data (in System.Data.dll)


Public NotInheritable Class SqlTriggerContext


Gets the number of columns contained by the data table bound to the trigger. This property is read-only.


Gets the event data specific to the action that fired the trigger.


Indicates what action fired the trigger.


Determines whether the specified object is equal to the current object.(Inherited from Object.)


Serves as the default hash function. (Inherited from Object.)


Gets the Type of the current instance.(Inherited from Object.)


Returns true if a column was affected by an INSERT or UPDATE statement.


Returns a string that represents the current object.(Inherited from Object.)

The contextual information provided includes the type of action that caused the trigger to fire, which columns were modified in an UPDATE operation, and, in the case of a data definition language (DDL) trigger, an XML EventData structure (see "Transact-SQL Reference" in SQL Server Books Online) that describes the triggering operation.

An instance of SqlTriggerContext is available from the SqlContext class, when the code is running inside a trigger through the TriggerContext property.

The following example shows a SqlTriggerContext object being used to determine if an Insert action occurred. If a row was inserted into the user's table, the user name and real name are retrieved from the inserted row and then added to the UserNameAudit table.

<SqlTrigger(Name:="UsersAudit", Target:="[dbo].[users]", Event:="FOR INSERT")> _
Public Shared Sub UsersAudit()

   Dim command As SqlCommand
   Dim triggContext As SqlTriggerContext
   Dim reader As SqlDataReader
   Dim userName As String
   Dim realName As String

   ' Get the trigger context.
   triggContext = SqlContext.TriggerContext        

   Select Case triggContext.TriggerAction

      Case TriggerAction.Insert

         ' Retrieve the connection that the trigger is using.
         Using connection As New SqlConnection("context connection=true")

            ' Get the inserted row.
            command = new SqlCommand("SELECT * FROM INSERTED;", connection)

            ' Get the user name and real name of the inserted user.                
            reader = command.ExecuteReader()
            userName = CType(reader(0), String)
            realName = CType(reader(1), String)


            ' Insert the user name and real name into the auditing table.
            command = New SqlCommand("INSERT [dbo].[UserNameAudit] (userName, realName) " & _
               "VALUES (@userName, @realName);", connection)

            command.Parameters.Add(new SqlParameter("@userName", userName))
            command.Parameters.Add(new SqlParameter("@realName", realName))


          End Using

   End Select

End Sub

.NET Framework
Available since 2.0

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Return to top
© 2016 Microsoft