Sayed Ahmed Just E.T.C Technologies Inc. Just E.T.C. Education Inc.
C++ is based on and an extension to C Knowing similarities and dissimilarities between C and C++ will help to select the right language for your application development
Comments: Header File: #include Namespace: A defined collection of symbols and variable names within an application The main () function: must have in a program Parentheses: A function/code block name is followed by Parentheses () Braces: Boundary of code blocks
Variables: Used to contain values. Think about variables in Mathematics Statements: An instruction to the computer hardware to perform specific action. Statement Terminator: a semicolon Function calls: One function can call another function. It's just a transfer of control from one code block to another code block. However, the control comes back to the caller again.
#include using namespace std; int main() { int studentId; count << "what is your student ID" << endl; cin>> studentId; count << "Student Id " << studentId << endl; }
A C++ program must have a namespace; C program ends with.c where C++ program ends with.cpp Information communication to and from c program is treated as stream. cout and cin are used for the purpose cout and cin are practically objects
To store values case sensitive must start with letter Supportted datatypes: char, int, float, double, boolean, wchar_t float: usually 32 bits - 6 digit after decimam, double: 64 bits - 10 digit after decimal,
Can be declared anywhere Local: inside functions Static: Inside functions but do not get destroyed after Global: Declared outside the functions can be accessed from anywhere in the program Formal/Parameter Hidden variable: if a local variable use the same name of a global variable the local variable = hidden variable use scope operator :: to access the global variable inside that function
Group of variable A group of variables of the same type in c strings are null terminated arrays C++ also supports a predefined string class/data type; include
in c, define XYZ 100 in c++, const int val=1000
Enables Code Resuse Enables Data Security from Unauthorized Access Object: Attribute + behaviors Primary OOP Concepts Encapsulation: Inheritance: - reduce development time - reuse -increase maintainability of the code Polymorphism: assign different uses to an entity based onthe context Abstraction: simple representation of an objet. hide not essential attributes and behaviors
Object Oriented Paradigm: Define objects - toughest define messages define properties --define attributes --define behaviors Object behavior analysis: Understand the application Derive Objects Categorize Objects Model process flow
C++ Compliers Must Support: ANSI Standard Internationalization Template Locales Namespaces
Friend Class Friend functions and inline functions provide faster, and efficient application A function can be friend to any number of functions Use function declaration to declare friend functions Static Data Members and Static Members Function - create the common members of classes (across objects)
Constructor no return types called at object creation Destructor no return type
Operator Overloading Compile time polymorphism runtime poly - inheritance virtual functions Operator Overloading: -unary -binary -arithmetic -assignment Note: C++ does not support overloading based on return type
Early Binding/Late Binding Access Modifiers absent = protected
inheritance and destructors Diamond Problem: Virtual Base Class Overriding Pure Virtual Function
manipulators COUT, setw, right, setfill, flush, endl fstreambase fstream ifstream ofstream
Mode of file opening ios::in ios::out Sscanf Read formatted file data ifstream fin.getLine() Random File Reading seekg seekp
I/O System Buffered file system Stream classes stream istream--_IO_istream_withassign ostream Iostream Cin is an instance of _IO_istream_withassign Instance of _IO_ostream_withassign cout cerr
Stream formatting flags Can be used with setf(), unsetf() ios::left ios::dec ios::fixed ios::oct ios::right ios::scientific ios::showbase ios::showpoint ios::showpos ios::uppercase
Unformatted input/output character character array strings use text buffer Can provide abstraction of the I/O device functions for unformatted input and output cin.read() cin.gcount() cout.write()
Files fstreambase opening, manipulating, closing fstream, ifstream, ofstream mode ios::app, ios::ate, ios::binary, ios::in, ios::out, ios::trunc fin.getline() Get pointers Random Operation Put pointers pointers Seekg() Seekp() Tellg() Tellp()
Handling Exceptions runtime errors Exceptions try and catch block throw statement Uncaught Exceptions Multiple Catch identified by operating systems if not handled passed to op system exception as int, char,class strings how it passes through functions Derived Class Exceptions catch block hierarchy place derived classes catch up
runtime with virtual functions shape -draw rect tri define overriding by placing function in each Show why virtual function needed? virtual base pointer runtime polymorphism pure virtual function Late binding base point to base - call derive function - runtime-dynamic
Templates create reusable code STL provides some foundational items --templatized functions and --classes These can be used to solve a variety of problems Some STL Elements Containers Algorithms Iterators STLs are compatible across operating systems
Containers Vectors Lists Maps Containers Sequence Associative
Algorithms function templates work with container templates of any type algorithm header file Iterators are objects to cycle through the containers iterator header file needs to be included if iterators are used Iterator type: Random Access Bidirectional Forward Input Output
Vector and Array Comparison container - behave the same way - infinite
Lists: class Bidirectional linear sequentially Functions begin() end() erase() insert(); (template) push_back(); push_front(); remove(); splice();
Associative Container Map templates take two parameters Functions: begin(); clear(); count(); empty(); end(); erase(); insert(); size()
Working with Templates Imagine a situation - complex + many data type Overload may help but time consuming template can help object creation define data type template overloading