**Course Title:** Swift Programming: From Basics to Advanced Development **Section Title:** Control Flow and Functions **Topic:** Conditional statements: if, else, switch. **Introduction:** In the previous sections, we covered the basics of Swift programming, including variables, data types, and operators. Now, it's time to explore control flow statements, which allow your program to make decisions and execute different paths of code based on certain conditions. In this topic, we'll delve into the world of conditional statements, focusing on if, else, and switch statements. **What are Conditional Statements?** Conditional statements are used to execute a block of code if a certain condition is met. They allow your program to make decisions and adapt to different situations. In Swift, there are three primary types of conditional statements: if, else, and switch. ### 1. If Statement The if statement is the most basic conditional statement in Swift. It checks a condition and executes a block of code if the condition is true. **Syntax:** ```swift if condition { // code to execute if condition is true } ``` **Example:** ```swift let age = 25 if age >= 18 { print("You are eligible to vote") } ``` In this example, the if statement checks if the age variable is greater than or equal to 18. If true, it prints "You are eligible to vote" to the console. ### 2. If-Else Statement The if-else statement is used to execute one block of code if a condition is true and another block of code if the condition is false. **Syntax:** ```swift if condition { // code to execute if condition is true } else { // code to execute if condition is false } ``` **Example:** ```swift let grade = 85 if grade >= 90 { print("You got an A") } else { print("You didn't get an A") } ``` In this example, the if-else statement checks if the grade variable is greater than or equal to 90. If true, it prints "You got an A". If false, it prints "You didn't get an A". ### 3. Switch Statement The switch statement is used to execute different blocks of code based on the value of a variable. **Syntax:** ```swift switch variable { case value1: // code to execute if variable is value1 case value2: // code to execute if variable is value2 default: // code to execute if variable doesn't match any case } ``` **Example:** ```swift let day = "Tuesday" switch day { case "Monday": print("Today is Monday") case "Tuesday": print("Today is Tuesday") case "Wednesday": print("Today is Wednesday") default: print("Today is not a weekday") } ``` In this example, the switch statement checks the value of the day variable. If it matches any of the cases, it prints the corresponding message. If it doesn't match any case, it prints "Today is not a weekday". **Key Concepts:** * Conditional statements are used to execute different paths of code based on certain conditions. * If statements are used to execute a block of code if a condition is true. * If-else statements are used to execute one block of code if a condition is true and another block of code if the condition is false. * Switch statements are used to execute different blocks of code based on the value of a variable. **Practical Takeaways:** * Use if statements when you want to execute a block of code if a condition is true. * Use if-else statements when you want to execute one block of code if a condition is true and another block of code if the condition is false. * Use switch statements when you want to execute different blocks of code based on the value of a variable. **Additional Resources:** * [Apple Documentation: Control Flow](https://docs.swift.org/swift-book/LanguageGuide/ControlFlow.html) * [Swift by Tutorials: Control Flow](https://www.raywenderlich.com/773094-swift-by-tutorials-control-flow) **Leave a Comment/Ask for Help:** If you have any questions or need help understanding a concept, feel free to leave a comment below. **What's Next:** In the next topic, we'll explore loops in Swift, including for-in loops, while loops, and repeat-while loops.