Swift

Strings

Understanding Strings in Swift

What is it?

A String is a series of characters, such as "hello" or "Swift programming". In Swift, strings are represented by the String type and are used to store and manipulate text.

Why does it exist?

Strings are fundamental because almost every program needs to work with text - displaying messages to users, processing user input, storing names, reading files, and communicating with servers. Without strings, we couldn't interact with users in a meaningful way.

Examples

Basic

Example 1

let greeting = "Hello, World!"

Creating a simple string variable

Intermediate

Example 1

let name = "Alice"
let message = "Hello, \(name)!"
print(message)  // Outputs: Hello, Alice!

String interpolation - embedding values inside strings

Advanced

Example 1

let multiline = """
    This is a
    multiline string
    """
let uppercased = multiline.uppercased()

Multiline strings and string methods

Common Mistakes

Common mistakes with strings:
1. Forgetting quotes: let text = Hello (Error! Must be "Hello")
2. Mixing quote types: let text = "Hello' (Error! Must match)
3. Not escaping special characters: let path = "C:
ew" (Error! Use "C:\new")
4. Treating strings like numbers: "5" + "3" = "53" (not 8!)

Write it once before proceeding

This helps your brain start forming the pattern.

Type this code:

let message = "Hello, World!"

Strings are like labels

Simple Explanation

Think of a string as a label or a note. Just like you might write your name on a label, a string is how computers remember text. Any word, sentence, or bunch of letters in quotes is a string.

Think of it like this

Imagine you have a label maker. When you type "School Books" and print it, that label is like a string - it's text you can stick anywhere, read, or change later.

Tiny Example

let name = "Emma"  // This stores the text "Emma" so the computer remembers it

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Strings

Understanding Strings in Swift

What is it?

Why does it exist?

Examples

Common Mistakes

Write it once before proceeding

Strings are like labels

Simple Explanation

Think of it like this

Tiny Example

Core Drill: Lock It In

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