Lesson 8Swift Basics

Strings

Strings in Swift

Strings are sequences of characters used to store text. Swift makes working with strings easy and powerful!

Creating Strings

  • Use double quotes: "Hello"
  • Join with +
  • Multi-line with """

Useful String Properties

.count

Number of characters

.isEmpty

Check if empty

.uppercased()

Convert to uppercase

.lowercased()

Convert to lowercase

String Methods

.hasPrefix()

Starts with?

.hasSuffix()

Ends with?

.contains()

Contains?

main.swift
// Creating strings
let greeting = "Hello"
let name = "Swift"

// Concatenation (joining strings)
let message = greeting + ", " + name + "!"
print(message) // Hello, Swift!

// String interpolation (inserting values)
print("\(greeting), \(name)!")

// Multi-line strings
let poem = """
    Roses are red,
    Violets are blue,
    Swift is awesome,
    And so are you!
    """
print(poem)

// String properties
let text = "Hello, World!"
print(text.count)          // 13 (character count)
print(text.isEmpty)        // false
print(text.uppercased())   // HELLO, WORLD!
print(text.lowercased())   // hello, world!

// String methods
print(text.hasPrefix("Hello"))  // true
print(text.hasSuffix("!"))      // true
print(text.contains("World"))   // true

// Loop through characters
for char in "Swift" {
    print(char)
}

Try It Yourself!

Create a greeting message with your name and print it in uppercase and lowercase!