Kindly need a macro to lock cell after a data entry

Kindly need a macro to lock cell after a data entry

Hi,
 
I am not very used to Zoho VBA and actually I am not good enough to write a macro from scratch.  I'm wondering if anyone would be so VERY kind as to show me the code needed for this problem : I'm trying to lock the cells automatically when data is entered. The code for Excel VBA should be like this : 

ActiveSheet.Unprotect ' Password:="secret"
    For Each cel In Target
        If cel.Value <> "" Then
            cel.Locked = True
        End If
    Next cel
    ActiveSheet.Protect ' Password:="secret"
End Sub

 
Best Regards,
Thomas