Programming | | Notes on the NULL ELSE, AND, and the OR Logical Operators:

The NULL ELSE: - is used when there is processing on the true path only. When the tested condition is not true, no special alternative action is required. The true path will perform some type of processing or output. The false path goes directly to the connector symbol. Having no condition after the keyword ELSE represents the no-function condition. It is immediately followed by the keyword ENDIF. Having the keyword ELSE is optional and in fact the program will still run if you do not apply it within the code. But it must be used if you do have information that must be processed in the false path. For good practice always apply the keyword ELSE within all programs that have the IFTHENELSE structure. Below you will see an example of a flowchart and a Visual Basic program.

Flowchart IFTHENELSE Null Example:

Logical Operators: are used to combine conditions in an IF statement. Logical operators that are commonly used include AND, OR, and NOT. The use of these logical operators is explained next.

The AND logical operator uses the word AND to mean two or more specified conditions are true in an expression. The program below will allow you to check to see if the two variables you entered are required. Depending on what hours and employee code you actually entered, the program will output a statement on both true and false paths.

The AND Logical Operators – For review only: You will NOT code the below Console Application just for review of this concepts.

The OR logical operator is used to indicate that if either or both conditions are true, then the IF statement is considered true and will follow the true path. Below shows how the OR operator can be applied within the IF Statement.

The OR Logical Operators – For review only: You will NOT code the below Console Application just for review of this concepts:

Adding Processing steps to this problem – For review only: You will NOT code the below Console Application just for review of this concepts:

Compute the pay for an employee, assuming that name, Employee's Code, and hours worked are as input. The output will be pay for the employee. You will notice that the steps to compute the employee's pay will be based on the same If statement.

Programming - Example Problem #8: (NULL ELSE, AND, and OR Operators):

Example Problem 8: This is a simple program that will use the IFTHENELSE structure that will allow the IF structure to make two or more combine conditions in a single IF statement. The example of the form will show a few textboxes, buttons and a few labels. Using the above structure and concepts to program this in a Window Application. Please remember to place your name somewhere at the bottom of this form and put a Flowerbox at the top of the code. Save the program as Example 8 and put the form and code together. Please Note: When turning in this Example problem 8 you will need to turn in the Form (during run time) and Code.

The NULL ELSE - Example 8A:

In this example problem you are testing to see if the employee worked 40 hours. In addition, you are to compare the flowchart with the code. Notice that there are no steps in the false path. This is called a NULL ELSE.

Example Problem 8B - You will write this Example Problem 8 by using the below code for this Window Application program. The above code was just to show how the Logical Operators can be used to test to or more inputs. This program will be written in Window Application. Here is a closer look at what the program code for this a Window Applications.

Below is the Example Problem 8B The code needed for this example problem.

Flowerbox Template: Put the flower box into the code as shown above.
[ Flower Box ]

Also please code the Clear and Exit Button in this program. Once you get the code entered try to run the program to get it working. Keep this simply by using the following Desk Check input below. Please note that you will need to type in a caps A, B, or C for the for the Employees Code. I also ask you to run it and test it many different ways. maybe try entering in a lower case a or b to see the output.

Notes The UCase and LCase Functions - Example Problem 8C: You will need to review these notes to see how UCase and LCase Functions is used with the code to make the program more user friendly.

Review the Link for the Example Problem 8C - You need to continue review the next set of code: Notes The UCase and LCase Functions- Example Problem 8C:.

The Desk Check - You will see three different desk check below. Once your program is running try to enter in the inputs to capture the output to the following and present the screen shots to this example problem.

Desk Check 1:
Enter your name as "Your Name"
Employee Code as: C (Note: use cap letter C)
Hours Worked: 10
Rate of Pay: 10
Your output should be $100 Desk Check 2:
Enter your name as "Your Name"
Employee Code as: A (Note: use cap letter A)
Hours Worked: 41
Rate of Pay: 10
Your output should be $615 Desk Check 3:
Enter your name as Keep blank
Employee Code as: Keep blank
Hours Worked: Keep blank
Rate of Pay: Keep blank
Your output should be Missing data above

Teacher Comment: So far you have learned quite a bit of some of the most important concepts of Basic programming. If you have understood everything so far, then well done. If you are a little skeptical and unsure, don't worry and keep an open mind and keep trying.

Directions for turning in Example problem - In the classroom: In this example problem you will have a print code and the screen shot (snipping Tool) for Example Problem 8. Once you get this output try to use the Snipping program to copy the screen shots and put it in a Word Document.
Three screen shots of the Form (during run time showing the data inputs and outputs)
The Code
Note: Flowchart of program is not needed

Directions for turning in Example problem 8 - Virtual: Virtual No Printing just upload the assignment files to Canvas Module 4 Example Problem 8. You will NOT need to print out any documents just submit this example problem in the Canvas drop box. Note you should have two screen shots: Example 8 Code, and the Form (Run Time screen). You will NOT need to produce a Flowchart with this example problem as the Form and Code is all that is needed. Put all screen shots (images) in a Word Document and send me the file. Save the Word document as the example problem: Example 8 and your first and last name.