获取数组元素位置

///////////////////////////////////////////////////

//获取数组元素位置

///////////////////////////////////////////////////

func findStringIndex(array:[String], valueToFind:String) -> Int?{

    for (index, value) in enumerate(array) {

            //println("\(index) \(value)")

        if value == valueToFind {

            return index

        }

    }

    return nil

}

 

let strings = ["cat", "dog", "llama", "parakeet", "terrapin"]

if let foundIndex = findStringIndex(strings, "llama") {

    println("The index of llama is \(foundIndex)")

}

//"The index of llama is 2

*/

 

/*

//不能直接在范型中使用“＝＝”需要Equatable来限制类型

func findIndex<T: Equatable>(array:[T],valueToFind:T) ->Int {

    for (index, value) in enumerate(array) {

        if value == valueToFind {

            return index

        }

    }

    return -1

}

let doubleIndex = findIndex([3.14159, 0.1,9.3,0.25], 9.3)

println(doubleIndex)

let stringIndex = findIndex(["Mike", "Malcolm", "Andrea"], "Andrea")

println(stringIndex)

/*

2

2

*/

*/