7

I want to be able to check when my array index goes out of range. The array elements are all strings, so I tried to do something like this but it doesn't work: 

if questions[3] != nil {
}

Can someone just show me how to check?

Henry Brown
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1 Answers1

11

Before indexing into the array, you need to check:

  1. The intended index is not below 0
  2. array's count is above the intended index
let intendedIndex: Int = 3

if (intendedIndex >= 0 && questions.count > intendedIndex) {
    // This line will not throw index out of range:
    let question3 = questions[intendedIndex]
}
AamirR
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Sergey Kalinichenko
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    not really Swift specific but obviously a working solution. Was hoping a bit for a Swift specific method or something but guess the is no such thing. – Blue Bot Oct 06 '20 at 09:57
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    So not to go far away by other links: if (questions.indices.contains(intendedIndex)) { ... } – Neph Muw Oct 13 '22 at 13:06