Professional C# and .NET, 2021st Edition

10Errors and Exceptions

WHAT'S IN THIS CHAPTER?

• Looking at the exception classes
• Using try…catch…finally to capture exceptions
• Filtering exceptions
• Creating user-defined exceptions
• Retrieving caller information

CODE DOWNLOADS FOR THIS CHAPTER

The source code for this chapter is available on the book page at www.wiley.com. Click the Downloads link. The code can also be found at https://github.com/ProfessionalCSharp/ProfessionalCSharp2021 in the directory 1_CS/ErrorsAndExceptions.

The code for this chapter is divided into the following major examples:

• SimpleExceptions
• ExceptionFilters
• RethrowExceptions
• SolicitColdCall
• CallerInformation

All the sample projects have nullable reference types configured.

HANDLING ERRORS

Errors happen, and they are not always caused by the person who coded the application. Sometimes your application generates an error because of an action that was initiated by the end user of the application, or it might be simply due to the environmental context in which your code is running. In any case, you should anticipate errors occurring in your applications and code accordingly.

.NET has enhanced the ways in which you deal with errors. C#'s mechanism for handling error conditions enables you to provide custom handling for each type of error condition and to separate the code that identifies errors from the code that handles them.

Your programs should be capable of handling any possible errors that might occur. For example, in the middle ...