After connecting to an application server and creating a Progress.Open4GL.Proxy.OpenAppObject, you can invoke application service code as follows:

  1. (Optional) In OpenEdge 12.3 and above, if it has been some time since a request and you want to ensure a server session is still valid, use the isConnected() method to Return the validity of the server session on an OpenAppObject.
  2. Run any external non-persistent, persistent, single-run, or singleton procedure that is available on the OpenAppObject. (Running a persistent, single-run, or singleton procedure instantiates an OpenProcObject.)
  3. Run any available internal procedure or user-defined function on an instantiated OpenProcObject.

    Before running any procedure or user-defined function, you must set up any parameters and return types required by the procedure or user-defined function. For more information, see Set up parameters and return types. You can then pass the parameters to the procedure or user-defined function and manage them according to their modes (INPUT, INPUT-OUTPUT or OUTPUT). For more information, see Pass parameters.

    After running any procedure or user-defined function, you must handle any output (returned values) or error conditions. For more information, see Handle returned values.

    The following sections describe:

    For examples that show how to run application service code, see Sample .NET OpenAPI code.