Displaying MsgBox when range of cells have not a specific length

[KevinMMO]

I have a program in which a label is scanned and that value goes into a cell, but for security reasons, it's necessary to check that the length of this is always the same (for example: 8, label=12345-78) the string has a "-" in it. What I want the program to do is that, when the scanned label has a number different than this one, display a messagebox that indicates that the number is invalid and then erase the cell's content. I would really appreciate some help with this.

 

[KevinMMO]

Code that reads cells and makes them string to apply condition

What I'm looking to do is a macro that reads a range of cells and if a string of numbers or letters different than 8 is pasted, display a message. There's a range from B9 to B20 where a scanner reads a label and inserts in order a number, so I'm also looking that it doesn't pay attention to blank cells in the range. I can't apply data validation since the data gets copied and not typed. Here's what I have so far:

Private Sub Worksheet_Change(ByVal Target As Range)



Dim i As Integer


On Error GoTo NoCells

i = Worksheets("HojadeInspection").Range("B9:B20").Cells. _
     SpecialCells(xlCellTypeConstants).Count

If Not Len(Range("B" & CStr(i))) = 8 Then

MsgBox "La longitud del dato insertado es incorrecta, revisar nuevamente", vbCritical



End If




NoCells:
Resume Next



    
End Sub