ConnectionEnumerator.Current Property

Статья
12/15/2008

Gets the current ConnectionManager object from the Connections collection.

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

Синтаксис

'Декларация
Public ReadOnly Property Current As ConnectionManager

public ConnectionManager Current { get; }

public:
property ConnectionManager^ Current {
    ConnectionManager^ get ();
}

/** @property */
public ConnectionManager get_Current ()

public function get Current () : ConnectionManager

Значение свойства

A ConnectionManager object.

Замечания

After an enumerator is created, or after a call to the Reset method, the MoveNext method must be called to advance the enumerator to the first element of the collection before reading the value of the Current property; otherwise, Current is undefined and throws an exception.

Current also throws an exception if the last call to MoveNext returned false, which indicates the end of the collection.

Current does not move the position of the enumerator, and consecutive calls to Current return the same object until either MoveNext or Reset is called.

An enumerator remains valid as long as the collection remains unchanged. If changes are made to the collection, such as adding, modifying, or deleting elements, the enumerator is invalidated and becomes irrecoverable; thus, the next call to MoveNext or Reset throws an InvalidOperationException. If the collection is modified between calls to MoveNext and Current, Current returns the element that it is set to, even if the enumerator has been invalidated.

Пример

The following code sample creates an enumerator, then uses the Current and MoveNext methods to navigate over the collection.

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

namespace ConnMgr_GetEnum_Current
{
    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 the application, and load the sample.
            Application app = new Application();
            Package pkg = app.LoadPackage(mySample, null);

            // Get the Connections collection from the package.
            Connections conns = pkg.Connections;
            
            //Create the Enumerator.
            ConnectionEnumerator myEnumerator = conns.GetEnumerator();
            Console.WriteLine("The collection contains the following values:");
            int i = 0;
            while ((myEnumerator.MoveNext()) && (myEnumerator.Current != null))
                Console.WriteLine("[{0}] {1}", i++, myEnumerator.Current.Name);
        }
    }
}

Imports System
Imports System.Collections.Generic
Imports System.Text
Imports Microsoft.SqlServer.Dts.Runtime
 
Namespace ConnMgr_GetEnum_Current
    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 the application, and load the sample.
            Dim app As Application =  New Application() 
            Dim pkg As Package =  app.LoadPackage(mySample,Nothing) 
 
            ' Get the Connections collection from the package.
            Dim conns As Connections =  pkg.Connections 
 
            'Create the Enumerator.
            Dim myEnumerator As ConnectionEnumerator =  conns.GetEnumerator() 
            Console.WriteLine("The collection contains the following values:")
            Dim i As Integer =  0 
            While (myEnumerator.MoveNext()) &&(myEnumerator.Current <> Nothing)
            Console.WriteLine("[{0}] {1}",i = Console.WriteLine("[{0}] {1}",i + 1
            End While
        End Sub
    End Class
End Namespace

Sample Output:

The collection contains the following values:

[0] localhost.AdventureWorks

[1] Transaction Summary by Product1

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