benday csharpninja slides

8/3/2019 BenDay CSharpNinja Slides

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How to be a C# ninjain 10 easy steps

Benjamin Day


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Benjamin Day Consultant, Coach, Trainer

Scrum.org Classes Professional Scrum Developer (PSD)

Professional Scrum Foundations (PSF)

TechEd, VSLive, DevTeach, OReilly OSCON

Visual Studio Magazine, Redmond Developer News Microsoft MVP for Visual Studio ALM

Team Foundation Server, TDD, Testing Best Practices,Silverlight, Windows Azure

http://blog.benday.com

[email protected]

Copyright 2011, Benjamin Day Consulting, Inc. www.benday.com 2


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1993-2011 Scrum.org, All Rights Reserved

Professional Scrum at Scrum.org

Professional

Scrum

Product Owner

Professional Scrum Foundations

Professional

Scrum Master

Professional

Scrum

Developer.NET or Java

Product OwnersExecutives

Scrum Masters

Architects

Business Analysts

DB SpecialistsDesigners

Developers

Testers

Everyone


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TOP 10 THINGS



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The List.1. Be humble

2. Object-orientation

3. Write less code

4. Value Types vs.Reference Types

5. Exceptions

6. Generics

7. Collections

8. IDisposable, using, &garbage collection

9. LINQ

10. Lambda Expressions



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Some extras.11.Virtual, override, &

new()12. Tune out the static

13.Partial classes &

methods14.Covarience

contravariance

15.Named parameters16.Optional parameters

17.Dynamic keyword



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BE HUMBLE.



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Be humble.

Software is complex.

We developers

want to please

think were awesome almost always underestimate



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Tips.

Keep it simple.

Expect to make mistakes.

Not everyone will understand your

abstractions. Favor maintainability over slickness.

Write unit tests. Lots of unit tests.



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C# doesnt do Xyz. C# sucks. Lesson I learned.

Theres a reason its built that way.

Dont fight it. Embrace it.

Learn from the design.



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RememberObject-Orientation



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Object-Oriented Principles 4 tenets

Encapsulation

Polymorphism Inheritance

Abstraction



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Save some typing.



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Less is more.(as long as its readable)



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Everything you write has to bemaintained.



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var vs. object



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Auto-Implemented Properties



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Read-OnlyAuto-Implemented Properties



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Avoid ternary operators



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VALUE TYPES VS.

REFERENCE TYPES



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Whuh?Value Types

Non-object types

Stored in memory stack

int, long, char, byte, etc.

float, double decimal

bool

User-defined Structs

Enumerations

Reference Types

Object types

Stored in memory heap

Variables are pointers to

memory location



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Boxing and Unboxing Boxing

Process of wrapping avalue type in an

object reference

Unboxing Converting a boxed value

type object back into an

value type variable



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EXCEPTION HANDLING



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Throw vs. throw exthrow; throw ex;



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GENERICS



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What are generics? Syntax that allows you to use similar

functionality with different types in a type-safe way

Implementation is the same

Data types are different



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ViewModelField

DomainObjectManager



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COLLECTIONS


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What is a Collection? Data type for organizing lists of objects

Similar to an array



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Part of the

.NETframework

5 namespaces



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Array vs. ListArray

Size defined whencreated

List

Automatically expands



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ArrayList vs. ListArrayList

Not type-safe

Everything is an object

Watch out for boxing /unboxing

List

Type-safe

Everything must be aninstance of T



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IDISPOSABLE, USING, AND

GARBAGE COLLECTION



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What is Garbage Collection? Background process in .NET

Determines when an object is not needed

Deletes it automagically

Frees up memory

You worry much less about memorymanagement.



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IDisposable



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IDisposable: Custom Cleanup Gets called when the Garbage Collector is

disposing your object Add custom logic

For example, close any open databaseconnections



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What does the

using statement do? Wraps instance of

IDisposable for blockof code

Instance is disposed

automatically at theend of the code block



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Wrap database connections

in using blocks

Most database classes implement

IDisposable



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Why should you wrap calls todatabase object in using

statements?



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LINQ



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LINQ Language-Integrated Query

Enables SQL-like querying of objects viaIEnumerable



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LINQ StuffOperators

select from

where

orderby

Useful functions

FirstOrDefault()

First()

Min()

Max()

Count()

Skip()

Take()

Reverse() Sum()



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(Code Demo: LinqSample.cs)



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LAMBDA EXPRESSIONS



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Whats a lambda expression? Anonymous functions

Helpful for delegates



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(Code Demos:LambdaExpressionSample.cs &

LambdaExpressionForm.cs)



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Additional Reading Essential C# 4.0

by Mark Michaelis

Great overview of the

language



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Additional Reading CLR via C#

by Jeffrey Richter

Whats going on

under the hood of C#and the .NETFramework



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The List.1. Be humble

2. Object-orientation3. Write less code

4. Value Types vs.

Reference Types5. Exceptions

6. Generics

7. Collections8. IDisposable, using, &

garbage collection

9. LINQ10. Lambda Expressions



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Thank you.

http://blog.benday.com | http://www.benday.com | [email protected]

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