DtsEventHandler.PrecedenceConstraints Property
Returns a collection of precedence constraints, if any, found on the executables in this container. This property is read-only.
Namespace: Microsoft.SqlServer.Dts.Runtime
Assembly: Microsoft.SqlServer.ManagedDTS (in Microsoft.SqlServer.ManagedDTS.dll)
Syntax
'Declaration
Public ReadOnly Property PrecedenceConstraints As PrecedenceConstraints
Get
'Usage
Dim instance As DtsEventHandler
Dim value As PrecedenceConstraints
value = instance.PrecedenceConstraints
public PrecedenceConstraints PrecedenceConstraints { get; }
public:
virtual property PrecedenceConstraints^ PrecedenceConstraints {
PrecedenceConstraints^ get () sealed;
}
abstract PrecedenceConstraints : PrecedenceConstraints
override PrecedenceConstraints : PrecedenceConstraints
final function get PrecedenceConstraints () : PrecedenceConstraints
Property Value
Type: Microsoft.SqlServer.Dts.Runtime.PrecedenceConstraints
A PrecedenceConstraints collection.
Implements
IDTSSequence.PrecedenceConstraints
Remarks
A PrecedenceConstraints collection is a collection of PrecedenceConstraint objects.
Examples
The following code example creates a DtsEventHandler for the OnError event in the package. This DtsEventHandler container contains two executables and establishes a precedence constraint between them. The code example displays the number of precedence constraints in the container.
using System;
using System.Collections.Generic;
using System.Text;
using Microsoft.SqlServer.Dts.Runtime;
using Microsoft.SqlServer.Dts.Tasks.SendMailTask;
using Microsoft.SqlServer.Dts.Tasks.BulkInsertTask;
namespace Microsoft.SqlServer.SSIS.Samples
{
class Program
{
static void Main(string[] args)
{
Package pkg = new Package();
// Set up a DtsEventHandler for the OnError event of the package.
DtsEventHandler dtsEH = (DtsEventHandler)pkg.EventHandlers.Add("OnError");
// Show the name and type of the properties in DtsEventHandler
// using the Properties collection.
DtsProperties props = dtsEH.Properties;
String name;
TypeCode propType;
foreach (DtsProperty prop in props)
{
propType = prop.Type;
name = prop.Name;
Console.WriteLine("Name {0}, Type {1}", name, propType);
}
// When an OnError Event occurs, the Executables collection contains
// the items to run. For this example, there will be a SendMailtTask
// and a BulkInsertTask with a precedence constraint between them.
Executable dtsEH1 = dtsEH.Executables.Add("STOCK:SendMailTask");
TaskHost th = (TaskHost)dtsEH1;
SendMailTask smTask = (SendMailTask)th.InnerObject;
smTask.Subject = "Send Mail task";
// Add a second executable to the DtsEventHandler.
Executable dtsEH2 = dtsEH.Executables.Add("STOCK:BulkInsertTask");
TaskHost th2 = (TaskHost)dtsEH2;
// Add a precedence constraint between the two tasks.
PrecedenceConstraint pc = dtsEH.PrecedenceConstraints.Add(dtsEH1, dtsEH2);
pc.Value = DTSExecResult.Completion;
// Review the number of constraints in the DtsEventHandler collection.
PrecedenceConstraints pcDTSEH = dtsEH.PrecedenceConstraints;
Console.WriteLine("Number of precedence constraints in DtsEventHandler: {0}", dtsEH.PrecedenceConstraints.Count);
// Review the number of executables in the DtsEventHandler collection.
Console.WriteLine("Number of executables in DtsEventHandler: {0}", dtsEH.Executables.Count);
// Remove the first executable in the DtsEventHandler collection.
dtsEH.Executables.Remove(0);
Console.WriteLine("New number of exeutables in DtsEventHandler: {0}", dtsEH.Executables.Count);
}
}
}
Imports System
Imports System.Collections.Generic
Imports System.Text
Imports Microsoft.SqlServer.Dts.Runtime
Imports Microsoft.SqlServer.Dts.Tasks.SendMailTask
Imports Microsoft.SqlServer.Dts.Tasks.BulkInsertTask
Namespace Microsoft.SqlServer.SSIS.Samples
Class Program
Shared Sub Main(ByVal args() As String)
Dim pkg As Package = New Package()
' Set up a DtsEventHandler for the OnError event of the package.
Dim dtsEH As DtsEventHandler = CType(pkg.EventHandlers.Add("OnError"), DtsEventHandler)
' Show the name and type of the properties in DtsEventHandler
' using the Properties collection.
Dim props As DtsProperties = dtsEH.Properties
Dim name As String
Dim propType As TypeCode
Dim prop As DtsProperty
For Each prop In props
propType = prop.Type
name = prop.Name
Console.WriteLine("Name {0}, Type {1}", name, propType)
Next
' When an OnError Event occurs, the Executables collection contains
' the items to run. For this example, there will be a SendMailtTask
' and a BulkInsertTask with a precedence constraint between them.
Dim dtsEH1 As Executable = dtsEH.Executables.Add("STOCK:SendMailTask")
Dim th As TaskHost = CType(dtsEH1, TaskHost)
Dim smTask As SendMailTask = CType(th.InnerObject, SendMailTask)
smTask.Subject = "Send Mail task"
' Add a second executable to the DtsEventHandler.
Dim dtsEH2 As Executable = dtsEH.Executables.Add("STOCK:BulkInsertTask")
Dim th2 As TaskHost = CType(dtsEH2, TaskHost)
' Add a precedence constraint between the two tasks.
Dim pc As PrecedenceConstraint = dtsEH.PrecedenceConstraints.Add(dtsEH1,dtsEH2)
pc.Value = DTSExecResult.Completion
' Review the number of constraints in the DtsEventHandler collection.
Dim pcDTSEH As PrecedenceConstraints = dtsEH.PrecedenceConstraints
Console.WriteLine("Number of precedence constraints in DtsEventHandler: {0}", dtsEH.PrecedenceConstraints.Count)
' Review the number of executables in the DtsEventHandler collection.
Console.WriteLine("Number of executables in DtsEventHandler: {0}", dtsEH.Executables.Count)
' Remove the first executable in the DtsEventHandler collection.
dtsEH.Executables.Remove(0)
Console.WriteLine("New number of exeutables in DtsEventHandler: {0}", dtsEH.Executables.Count)
End Sub
End Class
End Namespace
Sample Output:
Name CreationName, Type String
Name DelayValidation, Type Boolean
Name Description, Type String
Name Disable, Type Boolean
Name Executables, Type Object
Name ExecutionDuration, Type Int32
Name ExecutionResult, Type Object
Name ExecutionStatus, Type Object
Name Variables, Type Object
Number of precedence constraints in DtsEventHandler: 1
Number of executables in DtsEventHandler: 2
New number of exeutables in DtsEventHandler: 1