IEG 3080 Tutorial 1 Wilson Ip

Outline Lecture reviews: Some basics of Software Engineering principle Some basics of OOP How to use Visual Studio.NET 2005 Create a Project Console HelloWorld program Compile and Debugging tools

Lecture reviews: Software Engineering principle Potential challenges for building a complex large scale software Difficult to debug Unreliable software might be delivered. Users change the requirement A change might propagate throughout whole system Managing large team Inconsistencies in interpreting the requirement Difficult to merge the work done by independent individuals Difficult to maintain Maintaining the code from other teams/divisions/people who have been turnover Possibly more…

Lecture reviews: Software Engineering principle Solution Source or binary code reuse adopted the well-written code (but not allowed in assignments and project) Interface and Design Pattern reuse Make system flexible to change Facilitate future maintenance Setup a effective way of communication Precise documentation Visually model the software UML Software development Methodologies WaterFall Rational Unified Process Extreme Programming Regression tool NUnit

Lecture reviews: Software Engineering principle Dealing with a complex System Divide and Conquer Break a complex problem to simple problems Separation of Interface and Implementation Promote loose coupling, modularity, encapsulation and abstraction

Object Oriented Programming Traditional programming such as C: Sequence Condition – if, else if, else Repetition – loop Recursion Variables Divide big program into subroutines for modular structure OOP uses Objects for modular structure Object is (in programming): A module that encapsulates some internal state variables with a group of methods that alone have direct access to those variables. It can be used to model any real world/abstract objects

Object Oriented Programming Example objects in real world TV state - power, volume, contrast, brightness operation - turn on, turn off, vol_up, vol_down, … to change the state In modeling, pick out some properties from the real object to be modeled Example, to model a reader Attribute : name, status, max # of books, # of book lent, …. Action : lend, return, ….

Object Oriented Programming This shows an object in programming The internal attributes cannot be changed without carrying corresponding action. You cannot decrease the number of books lent without returning the books Actually, attributes will be internal state variables, actions are the methods. Name Status max # of books # of book lent Lend Return

Object Oriented Programming Class and Object Class – blueprint of an object, specify how the object will be built IF WE REALLY BUILD IT Object – really build the product by following what is specified by the class Instantiate an object = allocate memory for attributes, codes for the methods specified in the corresponding Class Analog for the relationship Class – Mold for producing the Moon cake Objects – The Moon cakes produced by this mold

Object Oriented Programming Constructor Constructor is used to initialize the attributes when the object is created Constructor is a function, its name is the same as that of the class Constructor has no return value There can be more than one constructor in the same class (By function overloading)

How to use Visual Studio.NET 2005 Create a project Menu -> file -> new -> project Choose “Visual C#” Choose “console application” Give a project name, say “308” Choose the location, say “C:\” Then, everything will be within the directory “C:\308”

How to use Visual Studio.NET 2005 Console HelloWorld program Function “Main” is the entry pt of the whole program (same as the main() in C/C++) “static” means that it can be called even no object is allocated, just like “Console.WriteLine” You can try to simply write a line “Console.WriteLine(“Hello World”); in Main Using System; Class HelloWorld { public static void Main() { Console.WriteLine(“Hello C# world”); }

How to use Visual Studio.NET 2005 Compile and Debugging Tools Compile Menu  Build  Build Solution After compile, execute without debugging Menu  Debug  Start Without Debugging Execute with debugging Menu  Debug  Start With Debugging Debugging functions: Step-by-step execution Insert breakpoint

How to use Visual Studio.NET 2005 Compile and Debugging Tools Step-by-step execution: choose Menu  Debug  “Step Into” continue to press Menu  Debug  “Step Into” to run only the current line of code and go one step to next execution line. The value of local variable with scope of execution line is shown in left bottom box You can view a particular variable by select the variable  right click  “add watch” If execution come to function call, it jump into the function If execution come to function call, press Menu  Debug  “Step over” to skip jumping into a function If execution inside a function block, press Menu  Debug  “Step out” to jump out one level from the function block.

How to use Visual Studio.NET 2005 Compile and Debugging Tools Menu  Debug  “Step Into”

How to use Visual Studio.NET 2005 Compile and Debugging Tools Menu  Debug  “Step over” Menu  Debug  “Step Out”

How to use Visual Studio.NET 2005 Compile and Debugging Tools Insert a breakpoint : Menu  Toggle breakpoint The program will be paused when it hits the break point. You can assign break point at any line in the program. Insert break point Menu  Start with Debugging Program pause at the break points

How to use Visual Studio.NET 2005 Compile and Debugging Tools You can break the program when some condition are fulfilled. E.g. The break point below is activated only if at the execution that satisfy TestVal2 < 20

Reference Wikipedia - Process Process