Error to validate the length of a barcode read

Question

I have a project in Visual Studio 2005 with EMDK 2.6 with a MC1000 data collector over XP SP3 implemented on Windows CE. I have this function within the project that gives me an error that I can't solve :

'Handle data from the reader
Private Sub HandleData(ByVal TheReaderData As Symbol.Barcode.ReaderData)
'MsgBox("Hello I'm reading ....")
If Me.DataTextBox.Text = "" Then
    Me.DataTextBox.Text = TheReaderData.Text
    ' Here begins the verification of the length
    If Len(Me.DataTextBox.Text) = Me.TextBox6.Text Then
        ' The length is ok
        objStreamWriter.WriteLine(Me.DataTextBox.Text)
        'Update the last read
        Me.Label5.Text = Me.DataTextBox.Text
        'Clean the field of the current read
        Me.DataTextBox.Text = ""
        'The counter of the code bars reads increases +1
        Me.TextBox3.Text = Me.TextBox3.Text + 1
    Else
        Me.DataTextBox.Text = ""
        MessageBox.Show("The length of the string read is not as expected", "Error !")
    End If
End If
End Sub

The problem begins when I read a barcode with a length different to Me.TextBox6.Text (24 for example), the messagebox is shows ok, but inmediatelly another message box appear with the next error: "StartRead Invalid Request Read already pending" and the program continues fine, I need to eliminate this error because looks very bad. Any help ? Thanks in advance.

Answer 1

MessageBox does not stop your application from processing other events and it may be that a new barcode is read (or the same barcode is notified again) while you are still in the function processing the previous one. Did you try to remove the call to MessageBox and check if this is still happening? You may need to disable the reader before you call MessageBox.