Question

我有一个工作表，上面已经添加了QR码。

QR码是ActiveX控件：Microsoft条码控件14.0

QR码链接到一个单元格（A1），因此，当单元格中的值更改时，QR码也会更改。

正常打开工作簿时，一切都会正常进行。

但是，当我使用vb.net Winforms项目中的Interop打开它时，当链接的单元格中的值更改时，QR码不再响应。而且，当我右键单击条形码控件时，“ Microsoft条形码控件14.0对象”上下文菜单选项（如下所示）丢失了。

我用来打开工作簿的互操作代码如下：

Dim XLApp As New Excel.Application
XLApp.Visible = True
Dim XLBook As Excel.Workbook = XLApp.Workbooks.Open(FilePath)

谁能告诉我是什么导致了这种情况的发生？也许建议我可以做些什么来防止它发生。

Answer 1

每次需要更新QR码时，都可以调用Calculate类的Worksheet方法。例如，VBA中的原始草图：

Application.EnableEvents = True
Application.ScreenUpdating = True
Sheets("QR_CodeSheet").Calculate

Answer 2

我无法使Microsoft条形码控件与interop一起正常运行。一种方法是使用shell命令打开文件，然后挂接到进程中以使用该文件。但是我发现这太混乱了。

相反，我决定使用Google的Chart API。这确实需要互联网连接。但这对我来说不是问题。

以下是更多信息的链接：https://sites.google.com/site/e90e50fx/home/generate-qrcode-with-excel

以及VBA代码：

Option Explicit
'other technical specifications about google chart API:
'https://developers.google.com/chart/infographics/docs/qr_codes

Function URL_QRCode_SERIES( _
    ByVal PictureName As String, _
    ByVal QR_Value As String, _
    Optional ByVal PictureSize As Long = 150, _
    Optional ByVal DisplayText As String = "", _
    Optional ByVal Updateable As Boolean = True) As Variant

Dim oPic As Shape, oRng As Excel.Range
Dim vLeft As Variant, vTop As Variant
Dim sURL As String

Const sRootURL As String = "https://chart.googleapis.com/chart?"
Const sSizeParameter As String = "chs="
Const sTypeChart As String = "cht=qr"
Const sDataParameter As String = "chl="
Const sJoinCHR As String = "&"

If Updateable = False Then
    URL_QRCode_SERIES = "outdated"
    Exit Function
End If

Set oRng = Application.Caller.Offset(, 1)
On Error Resume Next
Set oPic = oRng.Parent.Shapes(PictureName)
If Err Then
    Err.Clear
    vLeft = oRng.Left + 4
    vTop = oRng.Top
Else
    vLeft = oPic.Left
    vTop = oPic.Top
    PictureSize = Int(oPic.Width)
    oPic.Delete
End If
On Error GoTo 0

If Len(QR_Value) = 0 Then
    URL_QRCode_SERIES = CVErr(xlErrValue)
    Exit Function
End If

sURL = sRootURL & _
       sSizeParameter & PictureSize & "x" & PictureSize & sJoinCHR & _
       sTypeChart & sJoinCHR & _
       sDataParameter & UTF8_URL_Encode(VBA.Replace(QR_Value, " ", "+"))

Set oPic = oRng.Parent.Shapes.AddPicture(sURL, True, True, vLeft, vTop, PictureSize, PictureSize)
oPic.Name = PictureName
URL_QRCode_SERIES = DisplayText
End Function


Function UTF8_URL_Encode(ByVal sStr As String)    
    'http://www.nonhostile.com/howto-convert-byte-array-utf8-string-vb6.asp
    Dim i As Long
    Dim a As Long
    Dim res As String
    Dim code As String

    res = ""
    For i = 1 To Len(sStr)
        a = AscW(Mid(sStr, i, 1))
        If a < 128 Then
            code = Mid(sStr, i, 1)
        ElseIf ((a > 127) And (a < 2048)) Then
            code = URLEncodeByte(((a \ 64) Or 192))
            code = code & URLEncodeByte(((a And 63) Or 128))
        Else
            code = URLEncodeByte(((a \ 144) Or 234))
            code = code & URLEncodeByte((((a \ 64) And 63) Or 128))
            code = code & URLEncodeByte(((a And 63) Or 128))
        End If
        res = res & code
    Next i
    UTF8_URL_Encode = res
End Function


Private Function URLEncodeByte(val As Integer) As String
    Dim res As String
    res = "%" & Right("0" & Hex(val), 2)
    URLEncodeByte = res
End Function

通过互操作打开工作簿时，为什么Microsoft条码控制会中断？

2 个答案: