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Package.PrecedenceConstraints Property

Definition

Gets the collection of the PrecedenceConstraint objects. This field is read-only.

public:
 property Microsoft::SqlServer::Dts::Runtime::PrecedenceConstraints ^ PrecedenceConstraints { Microsoft::SqlServer::Dts::Runtime::PrecedenceConstraints ^ get(); };
public Microsoft.SqlServer.Dts.Runtime.PrecedenceConstraints PrecedenceConstraints { get; }
member this.PrecedenceConstraints : Microsoft.SqlServer.Dts.Runtime.PrecedenceConstraints
Public ReadOnly Property PrecedenceConstraints As PrecedenceConstraints

Property Value

The collection of the PrecedenceConstraint objects.

Implements

Examples

The following code example adds two tasks to the package, and places a precedence constraing between them. It then counts the number of constraints in the package collection.

using System;  
using System.Collections.Generic;  
using System.Text;  
using Microsoft.SqlServer.Dts.Runtime;  
using Microsoft.SqlServer.Dts.Tasks.FileSystemTask;  

namespace DataFlow_Conceptual  
{  
    class Program  
    {  
        static void Main(string[] args)  
        {  
            Package p = new Package();  
            // Add a File System task.  
            Executable eFileTask1 = p.Executables.Add("STOCK:FileSystemTask");  
            TaskHost thFileHost1 = eFileTask1 as TaskHost;  

            // Add a second File System task.  
            Executable eFileTask2 = p.Executables.Add("STOCK:FileSystemTask");  
            TaskHost thFileHost2 = eFileTask2 as TaskHost;  

            // Put a precedence constraint between the tasks.  
            // Set the constraint to be that thFileTask2 cannot run  
            // unless thFileTask1 completes.  
            PrecedenceConstraint pcFileTasks = p.PrecedenceConstraints.Add((Executable)thFileHost1, (Executable) thFileHost2);  
            pcFileTasks.Value = DTSExecResult.Completion;  

            // Return and show the count of precedence constraints in the package.  
            PrecedenceConstraints pCons = p.PrecedenceConstraints;  
            Console.WriteLine("Precedence constraints in package = {0}",  pCons.Count);  

        }  
    }  
}  
Imports System  
Imports System.Collections.Generic  
Imports System.Text  
Imports Microsoft.SqlServer.Dts.Runtime  

Namespace Package_API  
    Class Program  
        Shared  Sub Main(ByVal args() As String)  
            Dim app As Application =  New Application()   
            Dim pkg As Package =  New Package()   
            pkg = app.LoadPackage("C:\Program Files\Microsoft SQL Server\100\Samples\Integration Services\Package Samples\CalculatedColumns Sample\CalculatedColumns\CalculatedColumns.dtsx", Nothing)  

            ' Show the package type  
            Console.WriteLine("The package type is {0}", pkg.PackageType)  
        End Sub  
    End Class  
End Namespace  

Sample Output:

Precedence constraints in package = 1

Remarks

Returns the collection of PrecedenceConstraint objects that contain information about conditions that must occur before a step can be released for execution. For more information about precedence constraints, see Precedence Constraints.

Applies to