Handling Exception
Learn about handling exceptions in .NET using try-catch statements and provide customized error messages based on the exception type.
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Some languages return error codes when something goes wrong. .NET uses richer exceptions designed only for failure reporting. When this happens, we say a runtime exception has been thrown.
Other systems might use return values that could have multiple uses. For example, if the return value is a positive number, it might represent the count of rows in a table, or if the return value is a negative number, it might mean some error code.
try-catch statement
When an exception is thrown, the thread is suspended, and if the calling code has defined a try-catch statement, it is given a chance to handle the exception. If the current method does not handle it, then its calling method is given a chance, and so on up the call stack.
The default behavior of the console app
The default behavior of a console app or a .NET Interactive notebook is to output a message about the exception, including a stack trace, and then stop running the code. The application is terminated. This is better than allowing the code to continue executing in a potentially corrupt state. Our code should only catch and handle exceptions that it understands and can properly fix.
Wrapping error-prone code in a try block
When we know a statement can cause an error, we should wrap that statement in a try block. For example, parsing from text to a number can cause an error. Any statements in the ...