When using ProxyGen, you optionally can specify whether the ABL RETURN-VALUE should be added to the proxy method, for each non-persistent procedure and internal procedure. (User-defined functions always return a value.) If you specify this, the method returns string; otherwise, the method returns void. If specified for the non-persistent previous procedure, ProxyGen generates the following .NET proxy method:

public string AddCustomer(string name, string phone, string email, 
  out int CustomerNumber)

Also, if you did not specify that the ABL RETURN-VALUE should be returned, the client can access the current value of the ABL RETURN-VALUE function with the ProcReturnString property on the Open Client object. See Common properties for additional information.