为什么TextRange.InsertSymbol方法要替换TextRange中的文本？

Question

在通过powerpoint中的VBA生成幻灯片的过程中，我需要在生成的文本中插入一个"Wingdings符号“，这是两个值的比较。我做了这个方法，它完全符合我的要求。

Sub formatDifference(header As String, old As Integer, now As Integer, txt As TextRange)
    Dim diff As Integer
    diff = old - now

    With txt
        If (diff > 0) Then
            .InsertSymbol "Wingdings", getArrowCharCode("down")
                                       ' getArrowCharCode is a custom function to get the 
                                       ' char code as an Integer
        ElseIf (diff = 0) Then
            .InsertSymbol "Wingdings", getArrowCharCode("right")
        Else
            .InsertSymbol "Wingdings", getArrowCharCode("up")
        End If

        .InsertBefore header & now & " ("    ' <-- note this line
        .InsertAfter " " & Abs(diff) & ")"
    End With
End Sub

formatDifference Sub基本上只是在文本中添加一个符号点行(在下面的示例中，在添加非符号文本之前调用该过程4次)。

我不明白的是，当我用一些文本启动文本，然后使用InsertSymbol方法时，文本似乎实际上被替换了，而不是在末尾添加了符号。下面是一个不同代码的示例：

Sub formatDifference(header As String, old As Integer, now As Integer, txt As TextRange)
    Dim diff As Integer
    diff = old - now

    With txt
        .InsertAfter header & now & " (" ' <-- line moved here
                                         '     it doesn't matter if I use 
                                         '     .Text = "initial text"', 
                                         '     it will do the same thing
        If (diff > 0) Then
            .InsertSymbol "Wingdings", getArrowCharCode("down")
        ElseIf (diff = 0) Then
            .InsertSymbol "Wingdings", getArrowCharCode("right")
        Else
            .InsertSymbol "Wingdings", getArrowCharCode("up")
        End If
        .InsertAfter " " & Abs(diff) & ")"
    End With
End Sub

下面是我从上面的代码中得到的两个结果的比较(按相同的顺序)：

​

​

我对InsertSymbol方法的理解是，它会在最后一段末尾插入符号，但它看起来不像.我的第二个例子是错误的，还是我误解了对方法的描述？

P.S.注意到：标头参数保存了回车和行提要字符，这就是为什么第二次捕获在同一行上有所有的点，因为第一部分似乎被替换了。

Answer 1

我可以做一个似乎很好的解决办法。

Sub AppendSymbol(ByRef orig As TextRange, ByVal fontName As String, ByVal charCode As Integer, Optional ByVal position As Integer = -1)
    Dim strStart, strEnd As String

    If ((position < 0) Or (position >= Len(orig.text))) Then
        orig.Paragraphs(orig.Paragraphs.Count + 1).InsertSymbol fontName, charCode
        'this one just inserts the symbol at the end by forcing a new paragraph
    Else
        strStart = Left(orig.text, position)
        strEnd = Right(orig.text, Len(orig.text) - position)

        orig.Paragraphs(1).InsertSymbol fontName, charCode
        orig.InsertBefore strStart
        orig.InsertAfter strEnd
    End If
End Function

在这个子部分中，我基本上复制了原来的行，用符号替换它，然后在符号周围重新添加字符串。

我现在可以这样称呼它：

Private Sub displayTotal(ByRef para As TextRange, ByVal prevCompare As Testing)
    Dim arrowDirection As String
    Dim tempDifference As Integer

    tempDifference = p_total - prevCompare.Total
    para.InsertAfter "Number of elements : " & p_total & " ("

    'calling the Sub
    AppendSymbol para, "Wingdings", getWingdingArrowChar(getArrowDirection(tempDifference))

    para.InsertAfter " " & Abs(tempDifference) & ")"
    para.IndentLevel = 2
    para.ParagraphFormat.Bullet = msoFalse
End Sub

至于解释，阿瑟尔似乎发现了一些东西。该方法的实现显然类似于Word的实现，它需要在添加符号之前折叠文本范围。

在上面的自定义方法中，行orig.Paragraphs(orig.Paragraphs.Count + 1).InsertSymbol fontName, charCode基本上是通过在当前段落后面添加一个段落来强制当前段落折叠，这就是为什么InsertSybol方法随后按预期工作。