Intro Week 10

Constructors

A classes constructor is the method that is run when an instance of the class is created. If you do not provide a constructor the compiler provides one for you. The constructor is used to initiate all member properties. Unlike intrinsic types variables that are not initialized will be set to 0 or "" or null by the compiler in the default constructor.

The constructor allows you to set default values for the properties of the class. If you do not provide a constructor then a default constructor will be provided. The default constructor will initialize all of the properties in the class to empty/zero/null values.

constructor example

public class Dog
{
	public Dog()
	{
		//constructor code
	}
}

Simple Dog class with constructor

//Dog simple class definition
public class Dog
{
 	public string Name;		// the dog's name
	public int Age;			// the dog's age
	public int Weight;	// the dog's weight
	public string BarkSound;	// the sound of the dog's bark
	
	public Dog()
	{
		BarkSound = "Woof!!!";
	}

	public void Bark() { 
		//put bark code here
	}
	public void Eat() {
		//put eat code here 
	}
}

Console Example Dog.cs

OverLoading Constructors

Overloading a constructor allows object creation to happen in different ways with different parameters. The class can be overloaded to accept different parameters but each constructor method must have a unique parameter signature. Dog class with overloaded constructor

//Dog overloaded class definition
public class Dog
{
 	public string Name;		// the dog's name
	public int Age;			// the dog's age
	public int Weight;			// the dog's weight
	public string BarkSound;	// the sound of the dog's bark
	
	public Dog()
	{
		BarkSound = "Woof!!!";
	}
	public Dog(string newName)
	{
		Name = newName;
		BarkSound = "Woof!!!";
	}
	public Dog(string newName, string newBarkSound )
	{
		Name = newName;
		BarkSound = newBarkSound;
	}

	public void Bark() { 
		//put bark code here
	}
	public void Eat() {
		//put eat code here 
	}
        public string About() {
           string strAbout = "";
           strAbout += this.Name;
           strAbout += " " + this.Age;
           strAbout += " " + this.Weight;
           strAbout += " " + this.BarkSound;
           return strAbout;
        }

}

}

Console Example dogOverload.cs

Art as a windows app

Art history flash cards

Intro To Programming Art Flash Cards

As a windows app

http://iam.colum.edu/introtoprogramming/jeff/sp10/WindowsFormsApplicationArts.zip

Homework

Make the Art as a windows app into a testing app.