Swift Switch

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Use switch to match a value against patterns.

In Swift, a switch must list every choice, and it stops checking more choices after the first match.

Basic Switch

Match integer ranges and exact values.

Add default to handle remaining cases.

let grade = 82
switch grade {
case 90...100:
  print("A")
case 80..<90:
  print("B")
case 70..<80:
  print("C")
default:
  print("Below C")
}

This example categorizes a score using ranges in switch.

Note: Swift switch must be exhaustive. Use default to cover remaining cases.

Switch can match strings directly against literal cases.

let command = "start"
switch command {
case "start":
  print("Starting")
case "stop":
  print("Stopping")
default:
  print("Unknown")
}