UltraLite ActiveX User's Guide
  Understanding UltraLite ActiveX Development
    Error handling

Error handling in eMbedded Visual Basic

You can use the standard eMbedded Visual Basic error-handling features to handle errors. To enable error handling, use the On Error Resume Next statement. On Error Goto 0 causes errors to halt execution of your code.

The Err.Number property holds the SQLCODE value for an error. You can also get the last error using the ULConnection.LastErrorCode property.

One common area where errors need to be caught is in handling missing database files. In the following example, On Error Resume Next is in effect, so control flows to the next statement following the one causing the error. If the specified database does not exist, the Err object is loaded with the error number and description.

' eMbedded Visual Basic
On Error Resume Next
Err.Clear     ' Clear any previous errors
Set Connection = DBMgr.OpenConnection(udb)
If Err.Number <> 0 Then   ' Connection failed, no database?
  Err.Clear
  Set Connection = DBMgr.CreateDatabase(udb & usm)
  If Err.Number <> 0 Then
    MsgBox "Connect with " & udb & usm & " failed: " & Err.Description
    App.End
  End If
End If