INotifyingChangeApplierTarget.SaveChangeWithChangeUnits 方法
在衍生類別中覆寫時，會將包含變更單位變更的項目變更儲存至項目存放區。
命名空間: Microsoft.Synchronization
組件: Microsoft.Synchronization (在 microsoft.synchronization.dll)
語法
'宣告
Sub SaveChangeWithChangeUnits ( _
change As ItemChange, _
context As SaveChangeWithChangeUnitsContext _
)
'用途
Dim instance As INotifyingChangeApplierTarget
Dim change As ItemChange
Dim context As SaveChangeWithChangeUnitsContext
instance.SaveChangeWithChangeUnits(change, context)
void SaveChangeWithChangeUnits (
ItemChange change,
SaveChangeWithChangeUnitsContext context
)
void SaveChangeWithChangeUnits (
ItemChange^ change,
SaveChangeWithChangeUnitsContext^ context
)
void SaveChangeWithChangeUnits (
ItemChange change,
SaveChangeWithChangeUnitsContext context
)
function SaveChangeWithChangeUnits (
change : ItemChange,
context : SaveChangeWithChangeUnitsContext
)
參數
- change
要套用的項目變更。
- context
有關要套用之變更的資訊。
備註
實作器注意事項： 當包含在 context 中的動作是 Create 時，您必須以不可部分完成的方式儲存此項目變更。這表示，您必須成功儲存所有變更單位，或者必須捨棄整個項目變更。只能儲存部分變更單位時，可能會導致資料損毀。 當呼叫 RecordRecoverableErrorForChangeUnit 而且 context 是 Create 時，RecordRecoverableErrorForChangeUnit 就會擲回 CreateFailuresMustBeForEntireItemException。 如果在進行這個方法期間取消了同步處理，而且提供者已經套用部分變更單位，提供者就必須針對沒有套用的所有變更單位呼叫 RecordRecoverableErrorForChangeUnit。
範例
下列範例將示範如何在 SaveChangeWithChangeUnits 方法中處理一些最常見的 SaveChangeAction 值。
Public Sub SaveChangeWithChangeUnits(ByVal change As ItemChange, ByVal context As SaveChangeWithChangeUnitsContext) Implements INotifyingChangeApplierTarget.SaveChangeWithChangeUnits
' Enumerate the change units received and apply them by using the specified action.
For Each cuChange As ChangeUnitChange In change.ChangeUnitChanges
Select Case context.GetActionForChangeUnit(cuChange)
Case SaveChangeAction.Create, SaveChangeAction.UpdateVersionAndData
If True Then
' Update the item store and metadata store for the specified change unit.
Try
Dim cuData As String = DirectCast(context.ChangeData, String())(cuChange.ChangeUnitId.GetByteId())
_ContactStore.UpdateContactFromSync(change, cuChange, cuData)
Catch ex As Exception
Dim errData As New RecoverableErrorData(ex)
context.RecordRecoverableErrorForChangeUnit(cuChange, errData)
End Try
Exit Select
End If
Case SaveChangeAction.UpdateVersionAndMergeData
If True Then
' Merge actions are not supported by this implementation.
Throw New NotImplementedException("UpdateVersionAndMergeData is not supported.")
End If
Case SaveChangeAction.UpdateVersionOnly
If True Then
' Update only the version of this change unit in the metadata store.
Try
_ContactStore.UpdateContactVersion(change.ItemId, cuChange.ChangeUnitId, cuChange.ChangeUnitVersion)
Catch ex As Exception
Dim errData As New RecoverableErrorData(ex)
context.RecordRecoverableErrorForChangeUnit(cuChange, errData)
End Try
Exit Select
End If
Case SaveChangeAction.DeleteAndRemoveTombstone, SaveChangeAction.DeleteAndStoreTombstone
If True Then
' Delete actions are handled in SaveItemChange, so throw an exception.
Throw New InvalidOperationException("SaveChangeWithChangeUnits received a delete action.")
End If
Case Else
If True Then
Throw New ArgumentOutOfRangeException("SaveChangeWithChangeUnits received an out-of-range action.")
End If
End Select
Next
' Use the metadata storage service to save the knowledge as each change is applied. Saving knowledge as each change is applied is
' not required. It is more robust than saving the knowledge only after each change batch, because if synchronization is interrupted
' before the end of a change batch, the knowledge will still reflect all of the changes applied. However, it is less efficient because
' knowledge must be stored more frequently.
Dim updatedKnowledge As SyncKnowledge = Nothing
Dim updatedForgottenKnowledge As ForgottenKnowledge = Nothing
context.GetUpdatedDestinationKnowledge(updatedKnowledge, updatedForgottenKnowledge)
_ContactStore.ContactReplicaMetadata.SetKnowledge(updatedKnowledge)
End Sub
public void SaveChangeWithChangeUnits(ItemChange change, SaveChangeWithChangeUnitsContext context)
{
// Enumerate the change units received and apply them by using the specified action.
foreach (ChangeUnitChange cuChange in change.ChangeUnitChanges)
{
switch (context.GetActionForChangeUnit(cuChange))
{
case SaveChangeAction.Create:
case SaveChangeAction.UpdateVersionAndData:
{
// Update the item store and metadata store for the specified change unit.
try
{
string cuData = ((string[])context.ChangeData)[cuChange.ChangeUnitId.GetByteId()];
_ContactStore.UpdateContactFromSync(change, cuChange, cuData);
}
catch (Exception ex)
{
RecoverableErrorData errData = new RecoverableErrorData(ex);
context.RecordRecoverableErrorForChangeUnit(cuChange, errData);
}
break;
}
case SaveChangeAction.UpdateVersionAndMergeData:
{
// Merge actions are not supported by this implementation.
throw new NotImplementedException("UpdateVersionAndMergeData is not supported.");
}
case SaveChangeAction.UpdateVersionOnly:
{
// Update only the version of this change unit in the metadata store.
try
{
_ContactStore.UpdateContactVersion(change.ItemId, cuChange.ChangeUnitId, cuChange.ChangeUnitVersion);
}
catch (Exception ex)
{
RecoverableErrorData errData = new RecoverableErrorData(ex);
context.RecordRecoverableErrorForChangeUnit(cuChange, errData);
}
break;
}
case SaveChangeAction.DeleteAndRemoveTombstone:
case SaveChangeAction.DeleteAndStoreTombstone:
{
// Delete actions are handled in SaveItemChange, so throw an exception.
throw new InvalidOperationException("SaveChangeWithChangeUnits received a delete action.");
}
default:
{
throw new ArgumentOutOfRangeException("SaveChangeWithChangeUnits received an out-of-range action.");
}
}
}
// Use the metadata storage service to save the knowledge as each change is applied. Saving knowledge as each change is applied is
// not required. It is more robust than saving the knowledge only after each change batch, because if synchronization is interrupted
// before the end of a change batch, the knowledge will still reflect all of the changes applied. However, it is less efficient because
// knowledge must be stored more frequently.
SyncKnowledge updatedKnowledge;
ForgottenKnowledge updatedForgottenKnowledge;
context.GetUpdatedDestinationKnowledge(out updatedKnowledge, out updatedForgottenKnowledge);
_ContactStore.ContactReplicaMetadata.SetKnowledge(updatedKnowledge);
}
請參閱
參考
INotifyingChangeApplierTarget 介面
INotifyingChangeApplierTarget 成員
Microsoft.Synchronization 命名空間