Chapter 6: Working with Delegates, Events, and Exceptions

Question 1

Event Syntax

Answer 1

<accessibility><strong>event &lt;</strong>delegate&gt; <eventname></eventname></accessibility>

Question 2

How do you check for event subscribers?

Answer 2

if (eventHandler != null)

Question 3

The .net generic EvnetHandler delegate syntax.

Answer 3

public event EventHandler<ObjectEventArgs> eventName

This assumes that the first arguent will be the object publishing the event.

The second argument is the ObjectEventArgs EventArgs subclass to give more information to the handler

Question 4

Event Inheritance Quirk

Answer 4

Events can only be raised only from within the clas that declared it.

So best practice would have you create an OnEvent protected method to allow sub classes to call it.

Question 5

Try Catch

catch hierarchy

Answer 5

The catches will be executed top down, and only one will ever get executed.

Question 6

The “finally” section…

Answer 6

Always executes

Always

Question 7

SQL Exception property called “Class” fatal range?

Answer 7

20-25

Question 8

Exception.ToString() includes what?

Answer 8

The name of the exception class.

the Message property.

a stack trace

Question 9

When creating your own Exception what should you make sure to do (best practice)

Answer 9

Make sure the Exception is [Serializable]

Question 10

What are the three kinds of Exceptions?

Answer 10

Expression Lambdas

Statement Lambdas

and Async Lambdas

Question 11

What are the two Built-in Delegate Types

Answer 11

Action

Func

Question 12

Where does the return type exist in Func declarations?

Answer 12

The last argument.

Question 13

The gist of anonymous methods

Answer 13

delegates defined inline.