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ExtendedPropertyEnumerator.Current Property

Definition

Returns the current ExtendedProperty object from the collection.

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

Property Value

The current ExtendedProperty object.

Examples

The following code sample creates an enumerator, and 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 ExtendedProperties_Testing  
{  
    class Program  
    {  
        static void Main(string[] args)  
        {  
            // The package is one of the SSIS Samples.  
            string mySample = @"C:\Program Files\Microsoft SQL Server\100\Tools\Samples\1033\DataTransformationServices\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 Extended properties collection from the package.  
            ExtendedProperties myExtProps = pkg.ExtendedProperties;  
            //Create the Enumerator.  
            ExtendedPropertyEnumerator myEnumerator = myExtProps.GetEnumerator();  

            Console.WriteLine("The collection contains the following values:");  
            int i = 0;  
            ExtendedProperty myExtProp;  
            while ((myEnumerator.MoveNext()) && (myEnumerator.Current != null))  
            {  
                myExtProp = (ExtendedProperty)myEnumerator.Current;  
                Console.WriteLine("[{0}] {1}, {2}", i++, myExtProp.ID, myExtProp.DataType);  
                Console.WriteLine("------------------------------");  
            }  
            // Reset puts the index pointer before the beginning.  
            // Do not retrieve from the collection until MoveNext is called.  
            myEnumerator.Reset();  
            myEnumerator.MoveNext();  

            // Now that the enumerator has been reset, and moved to the  
            // first item in the collection, show the first item.  
            myExtProp = (ExtendedProperty)myEnumerator.Current;  
            Console.WriteLine("The first item in the enumerator after Reset:");  
            Console.WriteLine("{0}, {1}", myExtProp.ID, myExtProp.DataType);  
            Console.WriteLine();  
        }  
    }  
}  
Imports System  
Imports System.Collections.Generic  
Imports System.Text  
Imports Microsoft.SqlServer.Dts.Runtime  

Namespace ExtendedProperties_Testing  
    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\100\Tools\Samples\1033\DataTransformationServices\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 Extended properties collection from the package.  
            Dim myExtProps As ExtendedProperties =  pkg.ExtendedProperties   
            'Create the Enumerator.  
            Dim myEnumerator As ExtendedPropertyEnumerator =  myExtProps.GetEnumerator()   

            Console.WriteLine("The collection contains the following values:")  
            Dim i As Integer =  0   
            Dim myExtProp As ExtendedProperty  
            While (myEnumerator.MoveNext()) &&(myEnumerator.Current <> Nothing)  
                myExtProp = CType(myEnumerator.Current, ExtendedProperty)  
                Console.WriteLine("[{0}] {1}, {2}",i = Console.WriteLine("[{0}] {1}, {2}",i + 1  
                Console.WriteLine("------------------------------")  
            End While  
            ' Reset puts the index pointer before the beginning.  
            ' Do not retrieve from the collection until MoveNext is called.  
            myEnumerator.Reset()  
            myEnumerator.MoveNext()  

            ' Now that the enumerator has been reset, and moved to the  
            ' first item in the collection, show the first item.  
            myExtProp = CType(myEnumerator.Current, ExtendedProperty)  
            Console.WriteLine("The first item in the enumerator after Reset:")  
            Console.WriteLine("{0}, {1}", myExtProp.ID, myExtProp.DataType)  
            Console.WriteLine()  
        End Sub  
    End Class  
End Namespace  

Sample Output:

The collection contains the following values:

[0] {F3B7314E-DB1E-4CCA-A856-2E617A1B3265}, String

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

[1] {AA947F2D-C3B3-420F-B39E-4B7C77DAAFC0}, String

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

[2] {AB2CCC33-3090-4C36-B444-5B50BB481324}, String

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

[3] {FE85601C-4ECC-41D4-BEAA-1318DDF7EE2A}, String

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

[4] {4D1641B9-94EF-4144-9820-1B30ABD2214F}, String

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

[5] {4E76A01C-BFF8-462D-AAB0-FB48B3EEAE00}, String

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

[6] {A56842E2-11C1-487E-B670-33F25B534146}, String

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

The first item in the enumerator after Reset:

{F3B7314E-DB1E-4CCA-A856-2E617A1B3265}, String

Remarks

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 the enumerator can read 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.

Applies to