LogProvider.GetExpression(String) Méthode
Définition
Important
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Retourne une chaîne qui contient l’expression de la propriété spécifiée. Null signifie qu’aucune expression n’est affectée.
public:
virtual System::String ^ GetExpression(System::String ^ propertyName);
public string GetExpression (string propertyName);
abstract member GetExpression : string -> string
override this.GetExpression : string -> string
Public Function GetExpression (propertyName As String) As String
Paramètres
- propertyName
- String
Nom de la propriété dont vous souhaitez afficher l'expression.
Retours
Chaîne qui contient l’expression utilisée pour évaluer la propriété.
Implémente
Exemples
L’exemple suivant définit la propriété Description du fournisseur de journaux comme texte : « Il s’agit du journal pour... » avec le mois actuel et le jour ajoutés à la fin de la chaîne. Il valide ensuite le package, qui résout l’expression et enregistre la valeur dans la propriété spécifiée dans propertyName
. L’expression est également définie sur les expressions de la propriété lorsque le package est enregistré.
using System;
using System.Collections.Generic;
using System.Text;
using Microsoft.SqlServer.Dts.Runtime;
namespace LogProvider_Expression_Tests
{
class Program
{
static void Main(string[] args)
{
// The package is one of the SSIS Samples. The package was
// modified to log to the SSIS log provider for Text files
// and saved before loading into this code.
string mySample = @"C:\Program Files\Microsoft SQL Server\100\Samples\Integration Services\Package Samples\ExecuteProcess Sample\ExecuteProcess\UsingExecuteProcess.dtsx";
// Create the Application, and load the sample.
Application app = new Application();
Package pkg = app.LoadPackage(mySample, null);
// Get the LogProviders collection.
LogProviders logProvs = pkg.LogProviders;
// Get the "SSIS log provider for Text files"
// provider from the collection.
LogProvider textLogProv = logProvs["SSIS log provider for Text files"];
//Display the current description of this provider.
String currDescription = textLogProv.Description;
Console.WriteLine("Current description: {0}", currDescription);
// Set an expression. Only a few properties
// are available to have expressions. For Log Providers,
//current only the properties of ConfigString, Description,
// and Name take expressions.
DateTime dt = DateTime.Now;
String nowMonth = dt.ToString("m");
String newDesc = "\"This is the log for " + nowMonth + "\"";
textLogProv.SetExpression("Description", newDesc);
// Validate the package to set the expression
// onto the property.
Connections pkgConns = pkg.Connections;
DTSExecResult valResult = pkg.Validate(pkgConns, null, null, null);
if (valResult != DTSExecResult.Failure)
{
Console.WriteLine("Validation passed: {0}", valResult);
}
else
Console.WriteLine("Validation FAILED: {0}", valResult);
// Retrieve the log provider collections.
logProvs = pkg.LogProviders;
// Retreive the text log provider from the collection.
textLogProv = logProvs["SSIS log provider for Text files"];
// Check the expression, and verify that the name changed.
String logProvExpr = textLogProv.GetExpression("Description");
Console.WriteLine("The expression for Description is {0}", logProvExpr);
String newDescAfter = textLogProv.Description;
Console.WriteLine("The description is now: {0}", newDescAfter);
}
}
}
Imports System
Imports System.Collections.Generic
Imports System.Text
Imports Microsoft.SqlServer.Dts.Runtime
Namespace LogProvider_Expression_Tests
Class Program
Shared Sub Main(ByVal args() As String)
' The package is one of the SSIS Samples. The package was
' modified to log to the SSIS log provider for Text files
' and saved before loading into this code.
Dim mySample As String = "C:\Program Files\Microsoft SQL Server\100\Samples\Integration Services\Package Samples\ExecuteProcess Sample\ExecuteProcess\UsingExecuteProcess.dtsx"
' Create the Application, and load the sample.
Dim app As New Application()
Dim pkg As Package = app.LoadPackage(mySample, Nothing)
' Get the LogProviders collection.
Dim logProvs As LogProviders = pkg.LogProviders
' Get the "SSIS log provider for Text files"
' provider from the collection.
Dim textLogProv As LogProvider = logProvs("SSIS log provider for Text files")
'Display the current description of this provider.
Dim currDescription As String = textLogProv.Description
Console.WriteLine("Current description: {0}", currDescription)
' Set an expression. Only a few properties
' are available to have expressions. For Log Providers,
'current only the properties of ConfigString, Description,
' and Name take expressions.
Dim dt As DateTime = DateTime.Now
Dim nowMonth As String = dt.ToString("m")
Dim newDesc As String = """This is the log for " + nowMonth + """"
textLogProv.SetExpression("Description", newDesc)
' Validate the package to set the expression
' onto the property.
Dim pkgConns As Connections = pkg.Connections
Dim valResult As DTSExecResult = pkg.Validate(pkgConns, Nothing, Nothing, Nothing)
If valResult <> DTSExecResult.Failure Then
Console.WriteLine("Validation passed: {0}", valResult)
Else
Console.WriteLine("Validation FAILED: {0}", valResult)
End If
' Retrieve the log provider collections.
logProvs = pkg.LogProviders
' Retreive the text log provider from the collection.
textLogProv = logProvs("SSIS log provider for Text files")
' Check the expression, and verify that the name changed.
Dim logProvExpr As String = textLogProv.GetExpression("Description")
Console.WriteLine("The expression for Description is {0}", logProvExpr)
Dim newDescAfter As String = textLogProv.Description
Console.WriteLine("The description is now: {0}", newDescAfter)
End Sub
End Class
End Namespace
Exemple de sortie :
Description actuelle : Écrit des entrées de journal pour les événements dans un fichier CSV
Validation passée : Réussite
L’expression de description est « Il s’agit du journal pour le 06 janvier »
La description est maintenant : Il s’agit du journal pour le 06 janvier
Remarques
ConfigString propertyName
, Description ou Name. Pour le fournisseur de journaux, ceux-ci sont actuellement les trois seules propriétés qui peuvent utiliser une expression.