假设从B1单元格取值，在A1单元格中生成二维码，
那么，代码如下↓

Sub genBarCode()
    '清除已有二维码
    Call clearBarCode
    With ActiveSheet.OLEObjects.Add(ClassType:="BARCODE.BarCodeCtrl.1")
        .Object.Style = 11    '二维码样式
        .Object.Value = Range("B1").Value    '二维码内容
        '二维码大小和单元格A1相同
        .Height = Cells(1, 1).Height
        .Width = Cells(1, 1).Width
        .Left = Cells(1, 1).Left
        .Top = Cells(1, 1).Top
    End With
End Sub

Sub clearBarCode()
    Dim shp As Shape
    For Each shp In ActiveSheet.Shapes
        If shp.Type = 12 Then shp.Delete
    Next
End Sub

生成的二维码如下↓