IDTSPropertiesProvider.SetExpression Method

Статья
12/15/2008

Assigns the specified expression to the property. Specify null to remove an existing expression from the property.

Пространство имен: Microsoft.SqlServer.Dts.Runtime
Сборка: Microsoft.SqlServer.ManagedDTS (in microsoft.sqlserver.manageddts.dll)

Синтаксис

'Декларация
Sub SetExpression ( _
    propertyName As String, _
    expression As String _
)

void SetExpression (
    string propertyName,
    string expression
)

void SetExpression (
    String^ propertyName, 
    String^ expression
)

void SetExpression (
    String propertyName, 
    String expression
)

function SetExpression (
    propertyName : String, 
    expression : String
)

Параметры

propertyName
The name of the property to which to assign the expression.

expression
The expression.

Замечания

The propertyName can be any property available on the object.

Пример

The ConnectionManager class inherits from the IDTSPropertiesProvider interface. The following code example shows the ConnectionManager class using the SetExpression and GetExpression methods that it inherited.

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

namespace ConnMgr_Properties_Collection
{
    class Program
    {
        static void Main(string[] args)
        {
            // The package is one of the SSIS Samples.
            string mySample = @"C:\Program Files\Microsoft SQL Server\90\Samples\Integration Services\Package Samples\CalculatedColumns Sample\CalculatedColumns\CalculatedColumns.dtsx";

            // Create an application and load the sample.
            Application app = new Application();
            Package pkg = app.LoadPackage(mySample, null);
            Connections myConns = pkg.Connections;

            // Get the Properties collection from the connection manager.
            ConnectionManager myConnMgr = myConns[0];
            DtsProperties connProperties = myConnMgr.Properties;

            // View information about the RetainSameConnection property 
            // before setting it using the SetExpression method.
            Boolean hasProperty = connProperties.Contains("RetainSameConnection");
            Console.WriteLine("has RetainSameConnection? {0}", hasProperty);
            Object myValue = myConnMgr.Properties["RetainSameConnection"].GetValue(myConnMgr);
            String mySValue = myValue.ToString();
            Console.WriteLine("value before is {0}", mySValue);String myTrueString = "true";

            // Use SetExpression to set the value to true.
myConnMgr.Properties["RetainSameConnection"].SetExpression(myConnMgr, myTrueString);
            
            // Validate the package to set the expression on the property.
            DTSExecResult valResult = pkg.Validate(myConns, null, null, null);
            
            // Now that the value has been set, retrieve the value
            // and the expression.
            myValue = myConnMgr.Properties["RetainSameConnection"].GetValue(myConnMgr);
            mySValue = myValue.ToString();
            String myExpression = myConnMgr.Properties["RetainSameConnection"].GetExpression(myConnMgr);
            String mySExpression = myExpression.ToString();
            Console.WriteLine("value and expression is {0}, {1}", mySValue, mySExpression); 
        }
    }
}

Imports System
Imports System.Collections.Generic
Imports System.Text
Imports Microsoft.SqlServer.Dts.Runtime
 
Namespace ConnMgr_Properties_Collection
    Class Program
        Shared  Sub Main(ByVal args() As String)
        ' The package is one of the SSIS Samples.
        Dim mySample As String = "C:\Program Files\Microsoft SQL Server\90\Samples\Integration Services\Package Samples\CalculatedColumns Sample\CalculatedColumns\CalculatedColumns.dtsx"

        ' Create an application and load the sample.
        Dim app As New Application()
        Dim pkg As Package = app.LoadPackage(mySample, Nothing)
        Dim myConns As Connections = pkg.Connections

        ' Get the Properties collection from the connection manager.
        Dim myConnMgr As ConnectionManager = myConns(0)
        Dim connProperties As DtsProperties = myConnMgr.Properties

        ' View information about the RetainSameConnection property 
        ' before setting it using the SetExpression method.
        Dim hasProperty As [Boolean] = connProperties.Contains("RetainSameConnection")
        Console.WriteLine("has RetainSameConnection? {0}", hasProperty)
        Dim myValue As [Object] = myConnMgr.Properties("RetainSameConnection").GetValue(myConnMgr)
        Dim mySValue As String = myValue.ToString()
        Console.WriteLine("value before is {0}", mySValue)
        Dim myTrueString As String = "true"

        ' Use SetExpression to set the value to true.
myConnMgr.Properties("RetainSameConnection").SetExpression(myConnMgr, myTrueString)

        ' Validate the package to set the expression on the property.
        Dim valResult As DTSExecResult = pkg.Validate(myConns, Nothing, Nothing, Nothing)

        ' Now that the value has been set, retrieve the value
        ' and the expression.
        myValue = myConnMgr.Properties("RetainSameConnection").GetValue(myConnMgr)
        mySValue = myValue.ToString()
        Dim myExpression As String = myConnMgr.Properties("RetainSameConnection").GetExpression(myConnMgr)
        Dim mySExpression As String = myExpression.ToString()
        Console.WriteLine("value and expression is {0}, {1}", mySValue, mySExpression) 
        End Sub
    End Class
End Namespace

Sample Output:

has RetainSameConnection? True

value before is False

value and expression is True, true

Синхронизация потоков

Any public static (Shared in Microsoft Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Платформы

Платформы разработки

Список поддерживаемых платформ см. в разделе Hardware and Software Requirements for Installing SQL Server 2005.

Целевые платформы