.net - 我可以在 Word 或 Excel 中创建撤消事务吗？ (VSTO)

Question

我注意到 Project 2007 具有允许将可撤消的操作放置在单个堆栈项或“撤消事务”中的功能。 For example:

Application.OpenUndoTransaction "Create 6 tasks"
Dim i As Integer
For i = 1 To 6
    ActiveProject.Tasks.Add "UndoMe " & i
Next
Application.CloseUndoTransaction 

这意味着用户可以在一次撤消操作中撤消所有操作，而不是 6 次。

这在 Word 和/或 Excel 中实现会很棒，因为我正在 VSTO 中做一些同时进行多项更改的操作，如果用户必须单击“撤消”，这对用户来说会有点烦人如果他们犯了错误，就多说几次。尽管这些特定功能似乎不存在，但有人知道是否/如何以某种方式完成此操作？

Answer 1

您可以通过覆盖 VBA 中的撤消和重做命令例程来模拟 Word 中的事务行为(不过，我认为单独使用 VSTO 不可能覆盖内置 Word 命令)。通过添加书签来标记事务的开始，通过删除书签来标记事务的结束。

当调用undo时，我们检查事务标记书签是否存在并重复undo直到标记消失。重做的工作方式相同。该机制支持对文档内容所做的所有修改的事务撤消/重做。但是，为了允许撤消/重做对文档属性的修改，需要使用 SetCustomProp 宏来实现特殊机制。文档属性不应直接设置，而只能通过此宏设置。

更新:我忘了明确提及，这种方法仅适用于键盘快捷键和菜单命令，单击工具栏按钮仍然会执行单步撤消。因此，我们决定用自定义按钮替换工具栏按钮。该代码已在 Word 2003 中使用了相当长一段时间(尚未在 Word 2007 中进行测试，因此请做好意外惊喜的准备；)

Option Explicit

' string constants for Undo mechanism
Public Const BM_IN_MACRO As String = "_InMacro_"

Public Const BM_DOC_PROP_CHANGE As String = "_DocPropChange_"
Public Const BM_DOC_PROP_NAME As String = "_DocPropName_"
Public Const BM_DOC_PROP_OLD_VALUE As String = "_DocPropOldValue_"
Public Const BM_DOC_PROP_NEW_VALUE As String = "_DocPropNewValue_"

'-----------------------------------------------------------------------------------
' Procedure : EditUndo
' Purpose   : Atomic undo of macros
'             Note: This macro only catches the menu command and the keyboard shortcut,
'                   not the toolbar command
'-----------------------------------------------------------------------------------
Public Sub EditUndo() ' Catches Ctrl-Z

    'On Error Resume Next
    Dim bRefresh As Boolean
    bRefresh = Application.ScreenUpdating
    Application.ScreenUpdating = False

    Do
        If ActiveDocument.Bookmarks.Exists(BM_DOC_PROP_CHANGE) Then
            Dim strPropName As String
            Dim strOldValue As String

            strPropName = ActiveDocument.Bookmarks(BM_DOC_PROP_NAME).Range.Text
            strOldValue = ActiveDocument.Bookmarks(BM_DOC_PROP_OLD_VALUE).Range.Text
            ActiveDocument.CustomDocumentProperties(strPropName).Value = strOldValue
        End If

    Loop While (ActiveDocument.Undo = True) _
       And ActiveDocument.Bookmarks.Exists(BM_IN_MACRO)

    Application.ScreenUpdating = bRefresh
End Sub

'-----------------------------------------------------------------------------------
' Procedure : EditRedo
' Purpose   : Atomic redo of macros
'             Note: This macro only catches the menu command and the keyboard shortcut,
'                   not the toolbar command
'-----------------------------------------------------------------------------------
Public Sub EditRedo() ' Catches Ctrl-Y

    Dim bRefresh As Boolean
    bRefresh = Application.ScreenUpdating
    Application.ScreenUpdating = False

    Do
        If ActiveDocument.Bookmarks.Exists(BM_DOC_PROP_CHANGE) Then
            Dim strPropName As String
            Dim strNewValue As String

            strPropName = ActiveDocument.Bookmarks(BM_DOC_PROP_NAME).Range.Text
            strNewValue = ActiveDocument.Bookmarks(BM_DOC_PROP_NEW_VALUE).Range.Text
            ActiveDocument.CustomDocumentProperties(strPropName).Value = strNewValue
        End If

    Loop While (ActiveDocument.Redo = True) _
       And ActiveDocument.Bookmarks.Exists(BM_IN_MACRO)

    Application.ScreenUpdating = bRefresh

End Sub

'-----------------------------------------------------------------------------------
' Procedure : SetCustomProp
' Purpose   : Sets a custom document property
'-----------------------------------------------------------------------------------
Public Function SetCustomProp(oDoc As Document, strName As String, strValue As String)

    Dim strOldValue As String

    On Error GoTo existsAlready
    strOldValue = ""
    oDoc.CustomDocumentProperties.Add _
        Name:=strName, LinkToContent:=False, Value:=Trim(strValue), _
        Type:=msoPropertyTypeString
    GoTo exitHere

existsAlready:
    strOldValue = oDoc.CustomDocumentProperties(strName).Value
    oDoc.CustomDocumentProperties(strName).Value = strValue

exitHere:
    ' support undo / redo of changes to the document properties
    'On Error Resume Next
    Dim bCalledWithoutUndoSupport  As Boolean

    If Not ActiveDocument.Bookmarks.Exists(BM_IN_MACRO) Then
        ActiveDocument.Range.Bookmarks.Add BM_IN_MACRO, ActiveDocument.Range
        bCalledWithoutUndoSupport = True
    End If

    Dim oRange As Range
    Set oRange = ActiveDocument.Range

    oRange.Collapse wdCollapseEnd
    oRange.Text = " "
    oRange.Bookmarks.Add "DocPropDummy_", oRange

    oRange.Collapse wdCollapseEnd
    oRange.Text = strName
    oRange.Bookmarks.Add BM_DOC_PROP_NAME, oRange

    oRange.Collapse wdCollapseEnd
    oRange.Text = strOldValue
    oRange.Bookmarks.Add BM_DOC_PROP_OLD_VALUE, oRange

    oRange.Collapse wdCollapseEnd
    oRange.Text = strValue
    oRange.Bookmarks.Add BM_DOC_PROP_NEW_VALUE, oRange

    oRange.Bookmarks.Add BM_DOC_PROP_CHANGE
    ActiveDocument.Bookmarks(BM_DOC_PROP_CHANGE).Delete

    Set oRange = ActiveDocument.Bookmarks(BM_DOC_PROP_NEW_VALUE).Range
    ActiveDocument.Bookmarks(BM_DOC_PROP_NEW_VALUE).Delete
    If Len(oRange.Text) > 0 Then oRange.Delete

    Set oRange = ActiveDocument.Bookmarks(BM_DOC_PROP_OLD_VALUE).Range
    ActiveDocument.Bookmarks(BM_DOC_PROP_OLD_VALUE).Delete
    If Len(oRange.Text) > 0 Then oRange.Delete

    Set oRange = ActiveDocument.Bookmarks(BM_DOC_PROP_NAME).Range
    ActiveDocument.Bookmarks(BM_DOC_PROP_NAME).Delete
    If Len(oRange.Text) > 0 Then oRange.Delete

    Set oRange = ActiveDocument.Bookmarks("DocPropDummy_").Range
    ActiveDocument.Bookmarks("DocPropDummy_").Delete
    If Len(oRange.Text) > 0 Then oRange.Delete

    If bCalledWithoutUndoSupport And ActiveDocument.Bookmarks.Exists(BM_IN_MACRO) Then
        ActiveDocument.Bookmarks(BM_IN_MACRO).Delete
    End If

End Function

'-----------------------------------------------------------------------------------
' Procedure : SampleUsage
' Purpose   : Demonstrates a transaction
'-----------------------------------------------------------------------------------
Private Sub SampleUsage()

    On Error Resume Next

    ' mark begin of transaction
    ActiveDocument.Range.Bookmarks.Add BM_IN_MACRO

    Selection.Text = "Hello World"
    ' do other stuff

    ' mark end of transaction
    ActiveDocument.Bookmarks(BM_IN_MACRO).Delete

End Sub