升級資料流程元件的版本
使用舊版元件建立的封裝可能包含不再有效的中繼資料，例如在新版元件中已修改其使用方式的自訂屬性。您可以覆寫 PipelineComponent 基底類別的 PerformUpgrade 方法，以更新之前儲存在舊封裝的中繼資料，從而反映元件的目前屬性。
[!附註]
當您為新版本的 Integration Services 重新編譯自訂元件時，如果未變更元件的屬性，就不必變更 DtsPipelineComponentAttribute..::..CurrentVersion 屬性的值。
範例
下列範例包含 2.0 版的虛構資料流程元件之程式碼。新版本號碼是定義在 DtsPipelineComponentAttribute 的 CurrentVersion 屬性中。該元件具有一個屬性，它定義如何處理超過臨界值的數值。在 1.0 版的虛構元件中，這個屬性名為 RaiseErrorOnInvalidValue 並接受 True 或 False 的布林值。在 2.0 版的虛構元件中，該屬性重新命名為 InvalidValueHandling 並接受自訂列舉的四個可能值之一。
下列範例中覆寫的 PerformUpgrade 方法會執行下列動作：
取得元件的目前版本。
取得舊的自訂屬性值。
移除自訂屬性集合中的舊屬性。
若有可能的話，根據舊屬性值設定新自訂屬性值。
將版本中繼資料設定成元件的目前版本。
[!附註]
資料流程引擎會在 pipelineVersion 參數中將自己的版本號碼傳遞至 PerformUpgrade 方法。此參數在 1.0 版的 Integration Services 中沒有用處，但是在後續版本中可能會變成有用。
範例程式碼只會使用兩個列舉值，以直接對應至自訂屬性之前的布林值。使用者可以透過元件的自訂使用者介面、在 [進階編輯器] 中或是以程式設計方式，選取其他可用的列舉值。如需有關在 [進階編輯器] 中顯示自訂屬性之列舉值的詳細資訊，請參閱＜資料流程元件的設計階段方法＞中的＜建立自訂屬性＞。
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;
}
}
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