Exceptions

C# has similar constructs as C++/Java for:
- throwing an exception,
- catching an exception.
Only a class derived from System.Exception can be used to represent an exception.
Like Java but unlike C++, C#'s try statement has an optional finally clause. When a try statement gets executed, the final piece of code to be executed will be the statements of the finally clause. These statements will be executed no matter whether an exception has occurred or not.
There is one important difference from Java. Suppose the code of a method includes a statement that can cause an exception to occur:
```
FileStream tFileStream = File.Open("data", FileMode.Open);
```
This can cause the FileNotFoundException exception.
Suppose the code of the method does not want to handle this exception.
In Java, the header of the method declaration must document that the execution of the method may cause an exception to occur:
```
private void iProcessFile() throws FileNotFoundException
{
    ...
}
```
In a .NET language, it is not necessary (and not possible) to do this.
One consequence is that, if you wish a method to catch all the exceptions that its code can throw, you cannot use the compiler to check whether you are doing this.