Welcome toVigges Developer Community-Open, Learning,Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
949 views
in Technique[技术] by (71.8m points)

exception handling - Why use finally in C#?

Whatever is inside finally blocks is executed (almost) always, so what's the difference between enclosing code into it or leaving it unclosed?

Question&Answers:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Answer

0 votes
by (71.8m points)

The code inside a finally block will get executed regardless of whether or not there is an exception. This comes in very handy when it comes to certain housekeeping functions you need to always run like closing connections.

Now, I'm guessing your question is why you should do this:

try
{
    doSomething();
}
catch
{
    catchSomething();
}
finally
{
    alwaysDoThis();
}

When you can do this:

try
{
    doSomething();
}
catch
{
    catchSomething();
}

alwaysDoThis();

The answer is that a lot of times the code inside your catch statement will either rethrow an exception or break out of the current function. With the latter code, the "alwaysDoThis();" call won't execute if the code inside the catch statement issues a return or throws a new exception.


与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome to Vigges Developer Community for programmer and developer-Open, Learning and Share
...