SqlTriggerContext Class

 

Provides contextual information about the trigger that was fired.

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

System.Object
  Microsoft.SqlServer.Server.SqlTriggerContext

public sealed class SqlTriggerContext

NameDescription
System_CAPS_pubpropertyColumnCount

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

System_CAPS_pubpropertyEventData

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

System_CAPS_pubpropertyTriggerAction

Indicates what action fired the trigger.

NameDescription
System_CAPS_pubmethodEquals(Object)

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

System_CAPS_pubmethodGetHashCode()

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

System_CAPS_pubmethodGetType()

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

System_CAPS_pubmethodIsUpdatedColumn(Int32)

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

System_CAPS_pubmethodToString()

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 static void UsersAudit()
{
   // Get the trigger context.
   string userName;
   string realName;
   SqlCommand command;
   SqlTriggerContext triggContext = SqlContext.TriggerContext;
   SqlDataReader reader;

   switch (triggContext.TriggerAction)
   {
      case TriggerAction.Insert:

      // Retrieve the connection that the trigger is using.
      using (SqlConnection connection
         = new SqlConnection(@"context connection=true"))
      {
         connection.Open();

         // 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();
         reader.Read();
         userName = (string)reader[0];
         realName = (string)reader[1];
         reader.Close();

         // 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));

         command.ExecuteNonQuery();               

      }

      break;
   }
}

.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.

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