PrecedenceConstraint.EvalOp Propiedad

public:
 property Microsoft::SqlServer::Dts::Runtime::DTSPrecedenceEvalOp EvalOp { Microsoft::SqlServer::Dts::Runtime::DTSPrecedenceEvalOp get(); void set(Microsoft::SqlServer::Dts::Runtime::DTSPrecedenceEvalOp value); };

[Microsoft.SqlServer.Dts.Runtime.Localization.LocalizablePropertyDescription(typeof(Microsoft.SqlServer.Dts.Runtime.Localized), "PCEvalOpDesc")]
public Microsoft.SqlServer.Dts.Runtime.DTSPrecedenceEvalOp EvalOp { get; set; }

[<Microsoft.SqlServer.Dts.Runtime.Localization.LocalizablePropertyDescription(typeof(Microsoft.SqlServer.Dts.Runtime.Localized), "PCEvalOpDesc")>]
member this.EvalOp : Microsoft.SqlServer.Dts.Runtime.DTSPrecedenceEvalOp with get, set

Public Property EvalOp As DTSPrecedenceEvalOp

Valor de propiedad

DTSPrecedenceEvalOp

Un valor de la enumeración DTSPrecedenceEvalOp.

Atributos

LocalizablePropertyDescriptionAttribute

Ejemplos

En el ejemplo de código siguiente se crean tres tareas y se conectan mediante restricciones de precedencia. A continuación, el ejemplo recorre en iteración las restricciones de la PrecedenceConstraints colección del paquete, imprimiendo información sobre cada restricción.

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

namespace PrecedenceConst  
{  
    class Program  
    {  
        static void Main(string[] args)  
        {  
            Package pkg = new Package();  
            // Add a File System task.  
            Executable eFileTask1 = pkg.Executables.Add("STOCK:FileSystemTask");  
            TaskHost thFileTask1 = eFileTask1 as TaskHost;  

            // Add a second File System task.  
            Executable eFileTask2 = pkg.Executables.Add("STOCK:FileSystemTask");  
            TaskHost thFileTask2 = eFileTask2 as TaskHost;  

            // Add a Bulk Insert task.  
            Executable eBulkInsert = pkg.Executables.Add("STOCK:BulkInsertTask");  
            TaskHost thBulkInsert = eBulkInsert as TaskHost;  

            // Add a precedence contraint between eFileTask1 and eFileTask2.  
            // Set the constraint to be that eFileTask2 cannot run   
            // until eFileTask1 completes.  
            PrecedenceConstraint pcFileTasks = pkg.PrecedenceConstraints.Add(eFileTask1, eFileTask2);  

            // Add another precedence contraint. Add it between eFileTask2 and BulkInsert.  
            // Again, set the constraint to be that BulkInsert cannot run   
            // until eFileTask2 completes.  
            PrecedenceConstraint pcFiletoBulk = pkg.PrecedenceConstraints.Add(eFileTask2, eBulkInsert);  

            // Obtain the precedence constraint collection, and display properties.  
            // Some properties are read/write and have not been set.  
            PrecedenceConstraints pConsts = pkg.PrecedenceConstraints;  
            foreach (PrecedenceConstraint pc in pConsts)  
            {  
                Console.WriteLine("Constrained container  {0}", pc.ConstrainedExecutable);  
                Console.WriteLine("Creation Name          {0}", pc.CreationName);  
                Console.WriteLine("Description            {0}", pc.Description);  
                Console.WriteLine("Evaluation operation   {0}", pc.EvalOp);  
                Console.WriteLine("Evaluates true         {0}", pc.EvaluatesTrue);  
                Console.WriteLine("Expression             {0}", pc.Expression);  
                Console.WriteLine("ID                     {0}", pc.ID);  
                Console.WriteLine("LogicalAnd             {0}", pc.LogicalAnd);  
                Console.WriteLine("Name                   {0}", pc.Name);  
                Console.WriteLine("Precedence Executable  {0}", pc.PrecedenceExecutable);  
                Console.WriteLine("Value                  {0}", pc.Value);  
                Console.WriteLine("-----------------------------------");  
            }  
        }  
    }  
}  

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

Namespace PrecedenceConst  
    Class Program  
        Shared  Sub Main(ByVal args() As String)  
            Dim pkg As Package =  New Package()   
            ' Add a File System task.  
            Dim eFileTask1 As Executable =  pkg.Executables.Add("STOCK:FileSystemTask")   
            Dim thFileTask1 As TaskHost =  eFileTask1 as TaskHost   

            ' Add a second File System task.  
            Dim eFileTask2 As Executable =  pkg.Executables.Add("STOCK:FileSystemTask")   
            Dim thFileTask2 As TaskHost =  eFileTask2 as TaskHost   

            ' Add a Bulk Insert task.  
            Dim eBulkInsert As Executable =  pkg.Executables.Add("STOCK:BulkInsertTask")   
            Dim thBulkInsert As TaskHost =  eBulkInsert as TaskHost   

            ' Add a precedence contraint between eFileTask1 and eFileTask2.  
            ' Set the constraint to be that eFileTask2 cannot run   
            ' until eFileTask1 completes.  
            Dim pcFileTasks As PrecedenceConstraint =  pkg.PrecedenceConstraints.Add(eFileTask1,eFileTask2)   

            ' Add another precedence contraint. Add it between eFileTask2 and BulkInsert.  
            ' Again, set the constraint to be that BulkInsert cannot run   
            ' until eFileTask2 completes.  
            Dim pcFiletoBulk As PrecedenceConstraint =  pkg.PrecedenceConstraints.Add(eFileTask2,eBulkInsert)   

            ' Obtain the precedence constraint collection, and display properties.  
            ' Some properties are read/write and have not been set.  
            Dim pConsts As PrecedenceConstraints =  pkg.PrecedenceConstraints   
            Dim pc As PrecedenceConstraint  
            For Each pc In pConsts  
                Console.WriteLine("Constrained container  {0}", pc.ConstrainedExecutable)  
                Console.WriteLine("Creation Name          {0}", pc.CreationName)  
                Console.WriteLine("Description            {0}", pc.Description)  
                Console.WriteLine("Evaluation operation   {0}", pc.EvalOp)  
                Console.WriteLine("Evaluates true         {0}", pc.EvaluatesTrue)  
                Console.WriteLine("Expression             {0}", pc.Expression)  
                Console.WriteLine("ID                     {0}", pc.ID)  
                Console.WriteLine("LogicalAnd             {0}", pc.LogicalAnd)  
                Console.WriteLine("Name                   {0}", pc.Name)  
                Console.WriteLine("Precedence Executable  {0}", pc.PrecedenceExecutable)  
                Console.WriteLine("Value                  {0}", pc.Value)  
                Console.WriteLine("-----------------------------------")  
            Next  
        End Sub  
    End Class  
End Namespace  

Salida del ejemplo:

Contenedor restringido Microsoft.SqlServer.Dts.Runtime.TaskHost

Nombre de creación

Descripción

Restricción de operación de evaluación

Evalúa true True

Expression

Id. {BA20A288-545D-4E48-864A-E6AF6C3B9AEE}

LogicalAnd True

Nombre {BA20A288-545D-4E48-864A-E6AF6C3B9AEE}

Ejecutable de precedencia Microsoft.SqlServer.Dts.Runtime.TaskHost

Valor correcto

-----------------------------------

Contenedor restringido Microsoft.SqlServer.Dts.Runtime.TaskHost

Nombre de creación

Descripción

Restricción de operación de evaluación

Evalúa true True

Expression

Id. {E8DBC95E-AF27-45D7-B961-17E908CC4530}

LogicalAnd True

Nombre {E8DBC95E-AF27-45D7-B961-17E908CC4530}

Ejecutable de precedencia Microsoft.SqlServer.Dts.Runtime.TaskHost

Valor correcto

-----------------------------------

Comentarios

Valores de la enumeración

Una restricción de precedencia vincula dos ejecutables: el ejecutable de precedencia y el ejecutable restringido. El ejecutable de precedencia se ejecuta antes del ejecutable restringido y el resultado de la ejecución del ejecutable de precedencia puede determinar si se ejecuta el ejecutable restringido. Si el resultado de ejecución del ejecutable de precedencia determina si el ejecutable restringido depende de esta configuración de propiedad.

Se aplica a