Programming Ch. 5
What happens to your code when you add a breakpoint?
A red dot will appear in the grey bar and the text will be highlighted in red.
Desk Checking 4 Things
Check Expected Input, Check Unexpected Output, Check Boundaries, Check Null
Insert Breakpoint with Vertical Bar
Click the gray vertical bar to the the left of your code window.
break mode
Debugger mode the application is in when execution stops at a breakpoint.
Runtime Errors
Errors that occur while your program runs. It is caused when your computer tries to carry out an impossible operation.
Step out
Exit the current programming block
When is the watch window displayed?
In breakmode
What are possible reasons for logic errors?
Incorrect formulas, all possible inputs not handled.
How do you write the statement to show a message box?
MessageBox.Show("Message","Title")
logic errors
Occur when the program compiles and executes, but the output is not what you wanted/expected.
Insert Break Point with Right Click
Right Click on Line of Code > Breakpoint > Insert Breakpoint
Pause
Stop here
syntax errors
Syntax errors occur when the programmer does not follow the rules of the programming language. Also called compilation errors or compiler errors.
When running the program, what happens when the breakpoint is reached?
The program will stop and wait on the coder.
How do you know you have a syntax error when looking at your code?
There is a blue wavy line under them to alert the programmer
What is the basic format of the Try..Catch?
Try Line(s) of code to check for exceptions Catch ex As Exception What to do if an exception is found Generally use a message box to alert user Finally (optional) Run this code if an exception is found or not End Try //End of the Statement
What happens when a runtime error is detected?
Your program stops running and a dialog box displays in the code editor window. Program goes into break mode.
What is Try..Catch
a function to check for incorrect user input.
program debugging
allowing for unexpected input from a user
Watch Window
allows the coder to track the value of variables as the program is being executed
What is the Local watch window?
automatic watch window at the bottom of your IDE.
desk checking
create a table of possible inputs and determine what the output should be.
Green Arrow
execute the rest of the program without stopping
programmer debugging
fixing errors
What is Numeric?
function used with an IF statement
Breakpoint
is a tool used by a programmer to isolate a section of code and watch how the complier steps through it.
Step Into
move to the next line of code in the programming block
How do you add variables to a watch window?
right click on the variables you want to "watch" select add watch the variable is added to the watch window
step over
skip the current programming block
Blue Square
stop the program and return to the IDE