What are the exception and error handling mechanisms in…

The exception and error handling mechanism in C++ is a system designed to manage unexpected situations that may occur during program execution. Exceptions refer to errors or exceptional situations that occur during program execution, such as dividing by zero or failing to allocate memory. The exception handling mechanism in C++ can capture and manage these exceptions to prevent program crashes or unpredictable results.

The key words and concepts of the exception handling mechanism in C++ mainly include the following.

1. try-catch block: used to catch and handle exceptions. The try block contains the code that may throw an exception, and the catch block is used to handle the caught exception.
2. Throw statement: It is used to raise an exception. When an exceptional situation occurs, you can use the throw statement to raise an exception and pass it to the try-catch block higher up for handling.
3. Exception class: In C++, exceptions can be passed by throwing exception objects. You can use standard library provided exception classes like std::exception, or you can create your own custom exception classes.
4. Exception handling order: When an exception occurs, the program will handle it in the order of nested try-catch blocks. If the catch statement in the current try block is unable to handle the exception, it will be passed on to the higher-level try-catch block for processing until a catch block that can handle the exception is found.
5. Unusual handling methods: Exceptions can be handled in a catch block by choosing to either recover from them, or continue to throw the exception.

The exception handling mechanism in C++ allows programs to handle exceptions appropriately when they occur, which can enhance the robustness and reliability of the program.