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Boolean Expressions in C#

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Boolean Expressions in C#

Boolean Expressions; if/else Control Structures; Values in Controls: text box, check box, radio buttons; Conditional operator:?; switch/case

A Boolean expression is one that can be evaluated as true or false.
A Boolean expression can use relational operators such as < for less than, > for greater than, == for equal, != for not equat and the logical operators && (and) and || (or).
In this lesson we will use the If and optional else statements to decide which statements to execute.

In order to do this you will:

• Evaluate Boolean expressions;
• Use if else control structure in calculations;
• Retrieve numeric values from text box;
• Use check boxes and radio buttons in an application;
• Recognize and be able to use the conditional operator;
• Write compound Boolean expressions;
• Be able to write code using the switch/case construct.

Please study the material at each of the links below.

1. Microsoft Reference: C# if/else, conditional operators, OR ||, AND &&, switch/case
   
   

2. Boolean Expressions: A Boolean expression is one that can be evaluated to true or false
   
   
3. if Statements: An if statement executes a group of statements only if certain conditions are true
   
   
4. Getting Numbers from Text Box: Numeric values in a text box must be parsed.
   
   
5. A buffet restaurant part 1: Adding radio buttons: A restaurant charges different prices for breakfast, lunch and dinner, dicounts.
   /csharp/videos/csharp-buffet1.mp4
   
6. A buffet restaurant part 2: Adding code for radio buttons and check boxes: Radio buttons and check boxes have a Boolean property checked
   /csharp/videos/csharp-buffet2.mp4
   
7. Rats in a maze: A few problems to solve using && and ||
   /videos/mousemaze.mp4
   
8. Left or Right?: On mouse move determine if the mouse is on left or right of form
   
   
9. Top or bottom?: On mouse move determine if the mouse is on top or bottom of form
   
   
10. Adding the Mouse Move Event: Shows the X and Y positions when the mouse moves on the form
    /csharp/videos/csharp-mousemove.mp4
    
11. Scrolling: Scrolls a label across the form on the Timer event
    /csharp/videos/csharp-scrolling.mp4
    
12. Letter Grade: Nested if/else to find letter grade
    /csharp/videos/csharp-nestedifelse.mp4
    
13. BMI: Body Mass Index: Nested if/else to find BMI Risk
    /csharp/videos/csharp-bmiRisk.mp4
    
14. The conditional operator: ?: The ? can be used for very simple Boolean expressions in place of if/else code
    
    
15. AND And OR: && means AND, || means OR
    
    
16. Drill on Boolean: Drill to test your understanding
    
    
17. Middle or Side: Determine if mouse is on the side or middle
    
    
18. Boolean Variables and Properties: Boolean values do not need to be compared to anything
    
    
19. switch/case: switch/case to show season
    /csharp/videos/csharp-season.mp4