From Errors Treatment to Exceptions Treatment Regarding the Execution Control over Visual Basic Programs

In order to comply with the quality standards and with the best practices, the execution of the professional programs must be rigorously controlled so that to avoid occurrence of unpredictable situations that might generate anomalies and could lead to computer blockage, forced termination of the execution and data loss. In traditional programming languages, including Visual Basic 6, the concept of error is extremely evolved. It is considered as error any situation in which the program fails to execute correctly, regardless if such anomaly is generated by a software or hardware cause. Nowadays the modern platforms, including VB.NET have introduced a new concept: exception. Unfortunately, perhaps by mistake, exception is assimilated by many IT specialists as an exceptional (extraordinary) situation or a rare situation.We agree with the opinion of those IT specialists asserting that error is strictly dependant on the programmer, when he/she fails in correctly generating the application’s structures, whilst exception is a situation not fitting in the usual natural execution or as desired by the programmer or user, without meaning that it occurs more often or more rarely.Designing robust programs implies for such not to terminate abnormally or block, not even upon receiving improper parameters. Two aspects are referred to: the behavior regarding low level errors (caused by the operation system, memory allocation, reading/writing in files or hardware malfunctions) and the reaction to the user’s errors, such as providing incorrect input data or incorrect use of operations in respect with their sequences. Notwithstanding what platform is used in designing the programs and regardless the controversy between the specialists, in order for the execution to be terminated under the program’s control, the commands that might generate anomalies and interruptions should be strictly monitored. Implicitly, the execution control should be handed over to specialized procedures, able to analyze the causes generating the anomaly and to launch into execution the most adequate remedy processes, or, as a last resort, to allow for the controlled termination of the program. These elements that are specific to Visual Basic programming are unitarily and systematically presented both by the traditional unstructured approach of errors and by the modern vision of structured exceptions’ approach, finally emphasizing the uncontestable advantages of the .NET platform.