Error Handling

Error handling covers those cases where something unintended happens, such as the user runing out of disk space, or the database server being unavailable. The try/catch error handling mechanism provides a way for you to "try" and execute some code, and "catch" any problems that occur and handle them programmatically.

If you are looking to handle errors in the validity of data in a data entry form, see the section on Validation.

Try/Catch

Exceptions are handled by what is known as a try/catch block. You bracket the code that can possibly throw an exception in a try { ... } block. Next, you follow this with one or more catch { ... } blocks where you put code that should execute when a specific or general type of exception is thrown. The following code snippet shows the framework for handling data exceptions: