Classes in C++ - Reading Assignment

C++ Programming
#485
  1. Why do we need classes, why can’t we just use structs? - classes allow us to assign functions that work with the data too.
  2. What are methods? - functions defined inside of a class are called member functions (or sometimes methods).
  3. How would you define a class? - they are a blueprint and describe what a resulting object will look like.
  4. What is an object? - it’s a variable within a class type.
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#486
  1. Why do we need classes, why can’t we just use structs?

classes provide functions that work with the data. structs just hold the data.

  1. *What are methods?

these are also called member functions. functions inside of the class(or struct).

  1. How would you define a class?

a class is a container that holds definitions of what an object will look like.

  1. What is an object?

an object is an element of a class.

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#487

1. Why do we need classes, why can’t we just use structs?
It’s preferable to use classes over structs as they provide space for member variables along with member functions.

2. What are methods?
Functions defined inside of a class are called methods.

3. How would you define a class?
A class is an encapsulation of data and procedures. It sets out what an object really looks like.

4. What is an object?
An object is a variable of class type.

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#488

1.With structs, we can only store data. With classes we can provide functions that works with data.

  1. Methods are functions defined in classes.
    1. class myClass {
      public:
      }
    1. An instance of a class
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#489

1.- They are more flexible than structs, they also provide functions instead of just data.

2.- Functions defined in classes.

3.- class className{
public:
private:
}

4.- An instance of a class.

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#490
  1. Classes define a user defined type that works with the data that it holds.
  2. Functions inside of a class is a method/member class. Methods can be defined either inside or outside of the class definition.
  3. class ThisClass { public: //insert code here }
  4. An object is a variable that must be defined in a class.
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#491

1. Why do we need classes, why can’t we just use structs?

Classes allow you to create functions that work with the data.

2. What are methods?

Functions created in classes are called methods.

3. How would you define a class?

class className {

};

4. What is an object?

For example an object is an instance of a class, but it can be many things.

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#492

  1. So data types not only hold data, but provide functions that work with the data as well.

  2. Functions defined inside of a class are called member functions / methods.

Class name {
Public
Int var1
Int var2
Void print ()
{
Std << cout << int var 1 << endl << int var 2 << endl;
}
};

  1. A variable is a class type

not 100 per cent on item 3

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#493

  1. Because structs can only store variables and data while class can use all that and functions so we can really do much more on class.

  2. Method function can be defined as inside or outside of the class.

3.Class for me is a template where we need an object to store value on it.

  1. Class and object works together where we use class as a template and we call object in the main and put values on it.
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#494

Not sure if autocorrect, but public, int, void and std keywords are lowercase. :slight_smile:

#495

Why do we need classes, why can’t we just use structs?
We could use only structs, but the advantage of classes is that we can include functions that will work specifically with our data structure. Use structs if we are only going to store data, use classes if we want to add more functionality to a struct.

What are methods?
Methods, or member functions, are the functions that will be included in the class atribute.

How would you define a class?
class ExampleClass{
public:
int a {};
double b {};
string c {};
…
};

What is an object?
An object of a class is a variable that has already been fully defined.
Here we are going to create the object today from the class Class with today’s date (yyyy, mm, dd) - Class today { 2021, 6, 11 };

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#496
  1. Structs only allow us to store related data, where as classes allow us to group the data and provides functionality.
  2. Methods are functions defined inside of a class.
  3. A class is defined by:
    class SomethingClass{------};
  4. An object is allocated memory to an instance of a class.
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#497

1- class not only holds data, but provide functions that work with the data as well. struct members and base classes/structs are public by default. class members and base classes/structs are private by default.

2-Methods, in other words member functions, are the functions defined inside of a class.

3- Since the members and the classes/structs are private by default, we have to write public
For example;

class exampleClass
{
public:
    int var1{};
    int var2{};
    int var3{};
 
    void exampleFunction(){

    }

};

4- An Object is an instance of a Class

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#498

  1. Why do we need classes, why can’t we just use structs?
    Structs contain variables and are used to store data; however classes provide functions that work with the data as well. In C++, this is typically done via the class keyword. The class keyword defines a new user-defined type called a class.

  2. What are methods?
    A class definition starts with the keyword class followed by the class name; and the class body, enclosed by a pair of curly braces.

Example:
class Box {
public:
double length; // Length of a box
double breadth; // Breadth of a box
double height; // Height of a box
};

  1. How would you define a class?
    A class is defined in C++ using keyword class followed by the name of class . The body of class is defined inside the curly brackets and terminated by a semicolon at the end.

  2. What is an object?
    A class provides the blueprints for objects, so basically an object is created from a class. We declare objects of a class with exactly the same sort of declaration that we declare variables of basic types.

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#499
  1. If we put functions inside our custom types, it’s better to use classes becaue using structs can cause problems, like not delocating memory space after use.
  2. Methods are functions inside classes and structs (member functions).
  3. A class is a special variable type, defined by the developer.
  4. An object is one instance of a class.
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#500
  1. Why do we need classes, why can’t we just use structs?

According to my understanding, there is no big difference between classes and structs in C++. The main difference is that all members of structs are by default only public but members of classes can be both public and private. However, it is a best practice to use structs for objects that only contain data and use classes for objects that hold both data and functions (although structs can also contain functions as members).

  1. What are methods?

Methods are functions that are defined inside of a class.

  1. How would you define a class?

A simple class that contains one integer variable and a function that prints that integer variable.

class ClassName
{
public:
    int id{};
    void classFunc(){
        std::cout << id <<  std::endl;
    }
};
  1. What is an object?

In the context of classes, a class represents the blueprint for any object that is derived from that particular class data type. The actual object is the construct created from this blueprint, hence the object has all the same characteristics as the blueprint (private/public members), and the object is the construct the user can actually interact with.

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#501

Why do we need classes, why can’t we just use structs?
It is better to use classes when it contains both member data and member functions. Due to memory allocation stuff.

What are methods?
methods are functions that are defined within the class declaration

How would you define a class?
Class

What is an object?
Class is a type of object

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#502
  1. Classes are able to work with functions.
  2. Functions defined inside of a class.
    3.class ClassName{
    //public:
    //private:
    }
  3. A variable of a class type.
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#503

FORUM QUESTIONS

  1. Why do we need classes, why can’t we just use structs?
    Classes and structs are very similar, however each have a few unique differentiations. The most notable difference is that a programmer can store functions inside of a class, but not in a struct…
    The ability to store functions inside the custom data type opens up the opportunity to perform methods in relation to data stored inside the class.
    Where a struct can bundle data, a class can bundle data and do things.

  2. What are methods?
    Methods (also known as member functions) are functions stored within classes that execute instructions. While the class can set out the structure of similar sets of data, a class can put this data into a relevant function.

  3. How would you define a class?
    A class is the blueprint for a data structure which holds variable placeholders and functions.
    A class doesn’t store data per se, however when a variable is created as a class, the data is stored under the structure set out by the class.

  4. What is an object?
    An object is an instance of a class. Where the class sets the blueprint for the data structure, an object is the data placed into this blueprint. The object is the entirety of the blueprint with the values.

ARTICLE QUESTIONS

  1. a) Create a class called IntPair that holds two integers. This class should have two member variables to hold the integers. You should also create two member functions: one named “set” that will let you assign values to the integers, and one named “print” that will print the values of the variables.
#include <iostream>

using namespace std;

class IntPair {
    public:
        int m_int1{};
        int m_int2{};

        void set(int int1, int int2) {
            m_int1 = int1;
            m_int2 = int2;
        }

        void print() {
            cout<< "Pair("<<m_int1<<", "<<m_int2<<")"<<endl;
        }
};

int main()
{
    IntPair p1;
	p1.set(1, 1);

	IntPair p2{2, 2};

	p1.print();
	p2.print();

	return 0;
}
  1. b) Why should we use a class for IntPair instead of a struct?
    The object makes use of both member data and methods (member functions). A function can not be part of a struct, therefore we use a class.
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#504

  1. Classes offer the possibility to define not only member variables but also member functions (also called methods) and are thereful more useful in certain circumstances where a member function is needed.

  2. Methods are member functions within a class.

  3. class Exampleclass
    {
    /member variables and functions/
    };

  4. an object is a variable of a certain class type. Following the example in point 3, a possible object using the class Exampleclass could be:
    Exampleclass class1{};

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