How to swap two items in an array using swapAt()

Paul Hudson    February 13th 2018    @twostraws

If you need to have two items in an array change places, the swapAt() method is exactly what you want: provide it two indexes inside your array, and the items at those positions will be swapped.

For example, consider this array:

var names = ["Paul", "John", "George", "Ringo"]

If I wanted John and Paul to swap places, I’d swap positions 0 and 1, like this:

names.swapAt(0, 1)

Note: swapAt() will trigger a fatal error if you try to swap beyond the length of the array.

Available from iOS 8.0

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