B CUSP 110B – Digital Thinking

Exercise 6: Defining and Using Functions

In this exercise we will practice with three aspects of working with functions in C#:

· Defining a function based on our needs

· Calling the function

· Defining a function that accepts parameters and experimenting with passing parameters

Please work with the person next to you, start with this source code. Download compile and run this program to see a simple bee where you cannot do anything with. Examine the source code: remember what we always do when examining source code:

· Look at variable declarations

· Variable initialization

· Variable update

Step 1: Defining a function to move the bee …

Define a new function:

After you have done with defining this function, compile and run, can you control your circle/bee now? Why not? Modify your code so that you can control the circle/bee with right thumbstick (arrow keys).

Here we see a function is defined/called at every Update!

Step 2: Define a function to be called conditionally. Let’s find a way for the bee to drop something …

Define a new function:

Now, let’s drop a new square every time Button-A is pressed:

Here, we defined a new behavior (drop the square), and only perform this behavior when the player tells us to.

Click the A-button (K-Key) a few times, not very interesting is it? All the squares landed in the exactly same place! No fun!!

Step 3: Well, let’s parameterize the dropping of square to the location of the bee!!

Let’s define a new function that parameterizes the dropping of squares …

Notice that this function drops a rectangle at the specified location (xPos, yPos). Now modify you code to call DropASquare() to (myCircle.CenterX, myCircle.CenterY) whenever the B-Button (L-Key) is clicked.

To Turn In
Nothing! BUT, show me what you have done, show me your implementation. Make sure I checked off your names before you leave to receive proper credit for this exercise!

Wrap Up

In this exercise you have practiced:

· defining a function

· calling the function you have defined

· passing parameters to a function