升级数据流组件的版本

示例

下面的示例包含 2.0 版本的虚拟数据流组件的代码。新的版本号在 DtsPipelineComponentAttribute 的 CurrentVersion 属性中定义。该组件具有一个用于定义如何处理超出阈值的数值的属性。在 1.0 版本的虚拟组件中，此属性名为 RaiseErrorOnInvalidValue 并接受布尔值 True 或 False。在 2.0 版本的虚拟组件中，已将属性重命名为 InvalidValueHandling 并接受来自自定义枚举的四个可能值中的一个。

下列示例中的已重写的 PerformUpgrade 方法将执行以下操作：

• 获取当前版本的组件。

• 获取原有自定义属性的值。

• 删除自定义属性集合中的原有属性。

• 基于原有属性的值设置新自定义属性的值（如果可能）。

• 将版本元数据设置为当前的组件版本。

注意
数据流引擎会将自己的版本号传递到 PerformUpgrade 方法的 pipelineVersion 参数中。此参数在 1.0 版本的 Integration Services 中没有任何用处，但是在后续版本中可能有用。

示例代码只使用直接映射到自定义属性的先前布尔值的两个枚举值。用户可以在高级编辑器中通过组件的自定义用户界面或以编程方式选择其他可用枚举值。有关在高级编辑器中显示自定义属性的枚举值的信息，请参阅数据流组件的设计时方法中的“创建自定义属性”。

Imports Microsoft.SqlServer.Dts.Pipeline
Imports Microsoft.SqlServer.Dts.Pipeline.Wrapper

<DtsPipelineComponent(ComponentType:=ComponentType.Transform, CurrentVersion:=2)> _
Public Class PerformUpgrade
  Inherits PipelineComponent

  ' Define the set of possible values for the new custom property.
  Private Enum InvalidValueHandling
    Ignore
    FireInformation
    FireWarning
    FireError
  End Enum

  Public Overloads Overrides Sub PerformUpgrade(ByVal pipelineVersion As Integer)

    ' Obtain the current component version from the attribute.
    Dim componentAttribute As DtsPipelineComponentAttribute = _
      CType(Attribute.GetCustomAttribute(Me.GetType, _
      GetType(DtsPipelineComponentAttribute), False), _
      DtsPipelineComponentAttribute)
    Dim currentVersion As Integer = componentAttribute.CurrentVersion

    ' If the component version saved in the package is less than
    '  the current version, Version 2, perform the upgrade.
    If ComponentMetaData.Version < currentVersion Then

      ' Get the current value of the old custom property, RaiseErrorOnInvalidValue, 
      ' and then remove the property from the custom property collection.
      Dim oldValue As Boolean = False
      Try
        Dim oldProperty As IDTSCustomProperty100 = _
          ComponentMetaData.CustomPropertyCollection("RaiseErrorOnInvalidValue")
        oldValue = CType(oldProperty.Value, Boolean)
        ComponentMetaData.CustomPropertyCollection.RemoveObjectByIndex("RaiseErrorOnInvalidValue")
      Catch ex As Exception
        ' If the old custom property is not available, ignore the error.
      End Try

      ' Set the value of the new custom property, InvalidValueHandling,
      '  by using the appropriate enumeration value.
      Dim newProperty As IDTSCustomProperty100 = _
        ComponentMetaData.CustomPropertyCollection("InvalidValueHandling")
      If oldValue = True Then
        newProperty.Value = InvalidValueHandling.FireError
      Else
        newProperty.Value = InvalidValueHandling.Ignore
      End If

    End If

    ' Update the saved component version metadata to the current version.
    ComponentMetaData.Version = currentVersion

  End Sub

End Class

using System;
using Microsoft.SqlServer.Dts.Pipeline;
using Microsoft.SqlServer.Dts.Pipeline.Wrapper;

[DtsPipelineComponent(ComponentType = ComponentType.Transform, CurrentVersion = 2)]
public class PerformUpgradeCS :
  PipelineComponent

  // Define the set of possible values for the new custom property.
{
  private enum InvalidValueHandling
  {
    Ignore,
    FireInformation,
    FireWarning,
    FireError
  };

  public override void PerformUpgrade(int pipelineVersion)
  {

    // Obtain the current component version from the attribute.
    DtsPipelineComponentAttribute componentAttribute = 
      (DtsPipelineComponentAttribute)Attribute.GetCustomAttribute(this.GetType(), typeof(DtsPipelineComponentAttribute), false);
    int currentVersion = componentAttribute.CurrentVersion;

    // If the component version saved in the package is less than
    //  the current version, Version 2, perform the upgrade.
    if (ComponentMetaData.Version < currentVersion)

    // Get the current value of the old custom property, RaiseErrorOnInvalidValue, 
    // and then remove the property from the custom property collection.
    {
      bool oldValue = false;
      try
      {
        IDTSCustomProperty100 oldProperty = 
          ComponentMetaData.CustomPropertyCollection["RaiseErrorOnInvalidValue"];
        oldValue = (bool)oldProperty.Value;
        ComponentMetaData.CustomPropertyCollection.RemoveObjectByIndex("RaiseErrorOnInvalidValue");
      }
      catch (Exception ex)
      {
        // If the old custom property is not available, ignore the error.
      }

      // Set the value of the new custom property, InvalidValueHandling,
      //  by using the appropriate enumeration value.
      IDTSCustomProperty100 newProperty = 
         ComponentMetaData.CustomPropertyCollection["InvalidValueHandling"];
      if (oldValue == true)
      {
        newProperty.Value = InvalidValueHandling.FireError;
      }
      else
      {
        newProperty.Value = InvalidValueHandling.Ignore;
      }

    }

    // Update the saved component version metadata to the current version.
    ComponentMetaData.Version = currentVersion;

  }

}