Arrays

Arrays

//Type inference 

var fruitList = ["apple", "banana"]

//Explicit format: 
var fruitList: Array<String> = ["apple", "banana"]
//Explicit shortcut format: 
var fruitList: [String] = ["apple", "banana"]

fruitList[1] = "orange"

//fruitList =["apple", "orange"]

Number of Items

println("The fruitList contains \(fruitList.count) items.")

//Console output: The fruitList contains 2 items.

Item Addition

fruitList[2] = "strawberry"

//Wrong: fatal error: Array index out of range

//Correct Method1: Use "append" to add item:

fruitList.append("strawberry")

//fruitList = ["apple", "orange", "strawberry"]

//Correct Method2: Use "+=":

fruitList += ("kiwifruit")

//fruitList = ["apple", "orange", "strawberry", "kiwifruit"]

//Insert an Item to a specific location

fruitList.insert("mango", atIndex: 2)

//fruitList = ["apple", "orange", "mango", "strawberry", "kiwifruit"]

Item Removal

fruitList.removeAtIndex(3)

//fruitList = ["apple", "orange", "mango", "kiwifruit"]

var removedItem = fruitList.removeLast()

//fruitList = ["apple", "orange", "mango"]

//removedItem = "kiwifruit"

Check if the array is empty:

if fruitList.isEmpty {

}

for loop: Iterating over the array

for itemCount in fruitList {

    println(itemCount)

}

//Console output:

apple

orange

mango

================================

Initialize an empty array

var intArray = [Int]()

//intArray is of type Int[]

println("intArray has \(intArray.count) items.")

//Console output: intArray has 0 items.

Add new item
intArray.append(2)

//intArray = [2]


Reset the array

intArray = []

Other method for creating arrays

var oneArray = Int[](count: 2, repeatedValue: 1)  //[1, 1]

var zeroArray = Int[](count: 3, repeatedValue: 0) //[0, 0, 0]

var combinedArray = oneArray + zeroArray          //[1, 1, 0, 0, 0]