Current-Eigenschaft

Syntax

'Declaration
Public ReadOnly Property Current As Object
    Get
'Usage
Dim instance As DtsEnumerator
Dim value As Object

value = instance.Current

public Object Current { get; }

public:
virtual property Object^ Current {
    Object^ get () sealed;
}

abstract Current : Object
override Current : Object

final function get Current () : Object

Implementiert

IEnumerator. . :: . .Current

Hinweise

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 Current; otherwise, Current is undefined.

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 therefore, 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 irrecoverably invalidated and the next call to MoveNext or Reset throws an InvalidOperationException. If the collection is modified between MoveNext and Current, Current will return the element that it is set to, even if the enumerator is already invalidated.

Beispiele

The following code example adds a task to a package then runs the package. The warnings collection is created by creating a WarningEnumerator, which inherits from this DtsEnumerator class, and displays each warning description using Current and MoveNext methods to review the warnings in the collection.

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

namespace Microsoft.SqlServer.SSIS.Samples
{
    class Program
    {
        static void Main(string[] args)
        {
            Package package = new Package();
            Console.WriteLine("Package warnings count before running: {0}", package.Warnings.Count);

            TaskHost taskH2 = (TaskHost)package.Executables.Add("STOCK:SendMailTask");
            taskH2.FailPackageOnFailure = false;
            taskH2.FailParentOnFailure = false;
            Console.WriteLine("SendMailTask: {0}", taskH2.ID);
 
            // Test that warnings were successfully added to the collection.
            package.MaximumErrorCount = 100;
            package.FailPackageOnFailure = false;
            package.FailParentOnFailure = false;
            package.DelayValidation = true;
            package.Execute();

            Console.WriteLine("Package warnings count after running the package: {0}", package.Warnings.Count);

            // Create the enumerator.
            WarningEnumerator myEnumerator = package.Warnings.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.Description);
        }
    }
}

Imports System
Imports System.Collections.Generic
Imports System.Text
Imports Microsoft.SqlServer.Dts.Runtime
Imports Microsoft.SqlServer.Dts.Tasks.ExecuteSQLTask
 
Namespace Microsoft.SqlServer.SSIS.Samples
    Class Program
        Shared  Sub Main(ByVal args() As String)
            Dim package As Package =  New Package() 
            Console.WriteLine("Package warnings count before running: {0}", package.Warnings.Count)
 
            Dim taskH2 As TaskHost = CType(package.Executables.Add("STOCK:SendMailTask"), TaskHost)
            taskH2.FailPackageOnFailure = False
            taskH2.FailParentOnFailure = False
            Console.WriteLine("SendMailTask: {0}", taskH2.ID)
 
            ' Test that warnings were successfully added to the collection.
            package.MaximumErrorCount = 100
            package.FailPackageOnFailure = False
            package.FailParentOnFailure = False
            package.DelayValidation = True
            package.Execute()
 
            Console.WriteLine("Package warnings count after running the package: {0}", package.Warnings.Count)
 
            ' Create the enumerator.
            Dim myEnumerator As WarningEnumerator =  package.Warnings.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:

Package warnings count before running: 0

SendMailTask: {34CAEFF9-64BF-401D-B646-C88B705DB971}

Package warnings count after running the package: 2

The collection contains the following values:

[0] The address in the From line is not formed correctly. It is missing an @ or it is not valid.

[1] Subject is empty

Siehe auch

Verweis