在C＃中捕获错误时退出程序？

Question

With Python, I normally check the return value. And, if there's an error, I use sys.exit() together with error message.

What's equivalent action in C#?

• Q1 : How to print out an error message to stderr stream?
• Q2 : How to call system.exit() function in C#?
• Q3 : Normally, how C# programmers process the errors? Raising and catching exceptions? Or, just get the return value and exit()?

Answer 1

Q1: In C#, you have to use System.Console.xxx in order to access the streams for input, output, and error: System.Console.Error is the standard error you can write to.

http://msdn.microsoft.com/en-us/library/system.console.aspx

Q2: You exit with:

System.Environment.Exit( exitCode );

http://msdn.microsoft.com/en-us/library/system.environment.exit.aspx

Q3: Yes, C# programmers raise (throw) exceptions (objects of classes deriving from the Exception class), and catch them in upper-level callers.

If you want to catch errors in the entire program, you just encapsulate the entire main() procedure in a try...catch:

class App {
    public static void Main(String[] args)
    {
        try {
            <your code here>
        } catch(Exception exc) {
            <exception handling here>
        }
        finally {
            <clean up, when needed, here>
        }
    }
}

Hope this helps.

Answer 2

Normally, you simply don't catch exceptions you can't handle. .NET takes care of killing your process for you.