ConfigurationEnumerator.Current 属性
定义
重要
一些信息与预发行产品相关，相应产品在发行之前可能会进行重大修改。 对于此处提供的信息，Microsoft 不作任何明示或暗示的担保。
从集合获取当前的 Configuration 对象。
public:
property Microsoft::SqlServer::Dts::Runtime::Configuration ^ Current { Microsoft::SqlServer::Dts::Runtime::Configuration ^ get(); };public Microsoft.SqlServer.Dts.Runtime.Configuration Current { get; }member this.Current : Microsoft.SqlServer.Dts.Runtime.ConfigurationPublic ReadOnly Property Current As Configuration属性值
集合中的当前元素。
示例
下面的代码示例创建一个 ConfigurationEnumerator，然后循环访问集合，其中显示了配置名称。
using System;
using System.Collections.Generic;
using System.Text;
using Microsoft.SqlServer.Dts.Runtime;
namespace Configurations_API
{
class Program
{
static void Main(string[] args)
{
Package p = new Package();
Configuration conf1 = p.Configurations.Add();
conf1.ConfigurationString = "Conf1 Configuration String";
conf1.ConfigurationType = DTSConfigurationType.EnvVariable;
conf1.Description = "Some description for Conf1 configuration";
conf1.Name = "Conf1";
conf1.PackagePath = "A Variable Name in configuration Conf1";
Configuration conf2 = p.Configurations.Add();
conf2.ConfigurationString = "Conf2 Configuration String";
conf2.ConfigurationType = DTSConfigurationType.ConfigFile;
conf2.Description = "Some description for Conf2 configuration";
conf2.Name = "Conf2";
conf2.PackagePath = "A Variable Name in configuration Conf2";
Configuration conf3 = p.Configurations.Add();
conf3.ConfigurationString = "Conf3 Configuration String2";
conf3.ConfigurationType = DTSConfigurationType.RegEntry;
conf3.Description = "Conf3 description for Conf3 configuration2";
conf3.Name = "Conf3";
conf3.PackagePath = "A Variable Name in configuration Conf3";
Configurations pkgConfigs = p.Configurations;
ConfigurationEnumerator myEnumerator = pkgConfigs.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 Configurations_API
Class Program
Shared Sub Main(ByVal args() As String)
Dim p As Package = New Package()
Dim conf1 As Configuration = p.Configurations.Add()
conf1.ConfigurationString = "Conf1 Configuration String"
conf1.ConfigurationType = DTSConfigurationType.EnvVariable
conf1.Description = "Some description for Conf1 configuration"
conf1.Name = "Conf1"
conf1.PackagePath = "A Variable Name in configuration Conf1"
Dim conf2 As Configuration = p.Configurations.Add()
conf2.ConfigurationString = "Conf2 Configuration String"
conf2.ConfigurationType = DTSConfigurationType.ConfigFile
conf2.Description = "Some description for Conf2 configuration"
conf2.Name = "Conf2"
conf2.PackagePath = "A Variable Name in configuration Conf2"
Dim conf3 As Configuration = p.Configurations.Add()
conf3.ConfigurationString = "Conf3 Configuration String2"
conf3.ConfigurationType = DTSConfigurationType.RegEnTry
conf3.Description = "Conf3 description for Conf3 configuration2"
conf3.Name = "Conf3"
conf3.PackagePath = "A Variable Name in configuration Conf3"
Dim pkgConfigs As Configurations = p.Configurations
Dim myEnumerator As ConfigurationEnumerator = pkgConfigs.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
示例输出：
集合包含以下值：
[0] Conf1
[1] Conf2
[2] Conf3
注解
创建枚举器或调用 Reset 方法后， MoveNext 必须调用该方法，才能在读取属性的值 Current 之前将枚举器推进到集合的第一个元素;否则， Current 未定义并引发异常。
Current如果最后一次调用返回MoveNextfalse，则也会引发异常，该调用指示集合的末尾。
Current不会移动枚举器的位置，并且连续调用以返回相同的对象，直到调用或MoveNextReset调用。
只要集合保持不变，枚举器就仍有效。 如果对集合进行了更改（例如添加、修改或删除元素），则枚举器将失效并变为不可恢复;因此，下一次调用 MoveNext 或 Reset 引发一个 InvalidOperationException。 但是，如果在调用 MoveNext 和 Current调用之间修改集合， Current 则返回它设置为的元素，即使枚举器已失效也是如此。