SCORE Sequence Choices to be made Once may not be enough Reuse and recycle Evaluate and improve

SCORESequenceChoices to be madeOnce may not be enoughReuse and recycleEvaluate and improve

We use procedures all of the timeThe fire drill on the wallA recipe in a cook book

They are set up in advanceWe use (call) them only as and when we need

them

Procedures in ASP.NETProcedure

Name

Code for the

procedure

It doesn’t matter how it works…So long as we know …

What the procedure does.

And

How to call the procedure.

In this case Call DisplayArray

Will draw the contents of the connect four game on the page.

Event ProceduresFor example, whenever you write the code

for a button, you are writing the code inside an event procedure.

E.g.

Private Sub btnOK_Click(ByVal sender As etc…

'code for the click event goes hereEnd Sub

Creating a Sub ProcedureMake sure

you are not creating a procedure inside a procedure!

One place you could use…

1. Start by typing …

2. Then press Enter…

3. Type your procedure code…

4. Call your procedure…

The Benefits of ProceduresGives greater functionalityHides complexityPromotes code re-useSimplifies maintenance

Gives greater functionality

We don’t need to write this code over and over again…

We call it with a single line of code..

Call DisplayArray

Hides complexityCall DisplayArray

Is very easy to typeVery simple to understand

Call DisplayArray =

Promotes code re-use(Library code)The code for connect four could be used

again in a game of noughts and crosses

Smart programmers build up code libraries so that useful procedures may be “recycled”

Simplifies maintenanceIf the code for a certain task exists only once

in a program

E.g. DisplayArray

Any changes to that one procedure are passed on to all the places in the program that call it.

Modifications and error corrections only need to be done once – within the procedure itself.

Flow of the code…Using the debugger we shall examine how the following code works when it calls the different procedures