adding an applicantID with string at first

[mheiy]

how can i add applicant id with a string like this one APP-0001 im using a database and when i click the button add it will generate a new applicant id. heres m code

With tbInquiry
    If .RecordCount = 0 Then
        txtAppID = "00000001"
    Else
        .MoveLast
        txtAppID = .Fields(0) + 1
'        txtAppInfo(0).SetFocus
    End If
End With