PropertyEnumerator.Current 属性
Returns the current DtsProperty element in the collection.
命名空间： Microsoft.SqlServer.Dts.Runtime
程序集： Microsoft.SqlServer.ManagedDTS（在 Microsoft.SqlServer.ManagedDTS.dll 中）
语法
声明
Public ReadOnly Property Current As DtsProperty
Get
用法
Dim instance As PropertyEnumerator
Dim value As DtsProperty
value = instance.Current
public DtsProperty Current { get; }
public:
property DtsProperty^ Current {
DtsProperty^ get ();
}
member Current : DtsProperty
function get Current () : DtsProperty
属性值
类型：Microsoft.SqlServer.Dts.Runtime.DtsProperty
A DtsProperty object.
注释
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. However, 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.
示例
The following code sample creates a PropertyEnumerator, then shows the use of the MoveNext and Current methods to move over the collection.
using System;
using System.Collections.Generic;
using System.Text;
using Microsoft.SqlServer.Dts.Runtime;
namespace DtsProperties_API
{
class Program
{
static void Main(string[] args)
{
Package pkg = new Package();
// Get the Properties collection from the package.
// This shows the default properties set on new packages.
DtsProperties pkgProperties = pkg.Properties;
// Create the enumerator.
PropertyEnumerator myEnumerator = pkgProperties.GetEnumerator();
// Show the use of the Contains method.
Boolean containsCertObj = pkgProperties.Contains("CertificateObject");
Console.WriteLine("Contains CertificateObject? {0}", containsCertObj);
// Show the use of the item[x] syntax.
String aName = pkgProperties[5].Name;
Console.WriteLine("Property 5 is {0}", aName);
// Show the use of the MoveNext and Current methods.
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 DtsProperties_API
Class Program
Shared Sub Main(ByVal args() As String)
Dim pkg As Package = New Package()
' Get the Properties collection from the package.
' This shows the default properties set on new packages.
Dim pkgProperties As DtsProperties = pkg.Properties
' Create the enumerator.
Dim myEnumerator As PropertyEnumerator = pkgProperties.GetEnumerator()
' Show the use of the Contains method.
Dim containsCertObj As Boolean = pkgProperties.Contains("CertificateObject")
Console.WriteLine("Contains CertificateObject? {0}", containsCertObj)
' Show the use of the item[x] syntax.
Dim aName As String = pkgProperties(5).Name
Console.WriteLine("Property 5 is {0}", aName)
' Show the use of the MoveNext and Current methods.
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:
Contains CertificateObject? True
Property 5 is Configurations
[0] CertificateContext
[1] CertificateObject
[2] CheckpointFileName
[3] CheckpointUsage
[4] CheckSignatureOnLoad
[5] Configurations
[6] Connections
[7] CreationDate
[8] CreationName
[9] CreatorComputerName
[10] CreatorName
[11] DelayValidation
. . .
[63] VersionGUID
[64] VersionMajor
[65] VersionMinor
[66] Warnings