Swift Tour Essay summary (4)

An example of Switch:

let vegetable = "red pepper"
switch vegetable {
case "celery":
    let vegetableComment = "Add some raisins and make ants on a log."
case "cucumber", "watercress":
    let vegetableComment = "That would make a agood tea sandwich."
case let x where x.hasSuffix ("pepper"):
    let vegetableComment = "Is it a spicy \ (x)?"
default:
    let vegetableComment = "Everything tastes good in soup."
}
Compared with the traditional oc, there are some new features, it is very practical to accept it

No break

for

for-in

let interestingNumbers = [
    "Prime": [2, 3, 5, 7, 11, 13],
    "Fibonacci": [1, 1, 2, 3, 5, 8],
    "Square": [1, 4, 9, 16, 25]
]
var largest = 0
for (kind, numbers) in interestingNumbers {
    for number in numbers {
        if number> largest {
            largest = number
        }
    }
}
largest
while / do while keep consistent

Extended usage of other for

var firstForLoop = 0
for i in 0..3 {
firstForLoop + = i
}
firstForLoop

var secondForLoop = 0
for var i = 0; i <3; ++ i {
    secondForLoop + = 1
}
secondForLoop
Used and applied… instead of .. contains upper value (the difference between <and <=)

Functions and Closures

func greet (name: String, day: String)-> String {
    returrn "Hellop \ (name), today is \ (day)."
}
greet ("Bob", "Tuesday")

// Use tuple to return multiple values
func getGasPrices ()-> (Double, Double, Double) {
    return (3.59, 3.69, 3.79)
}
getGasPrices ()
Func will use an array to collect multiple variables:

func sumOf (numbers: Int ...)-> Int {
    var sum = 0
    for number in numbers {
        sum + = number
    }
    return sum
}
sumOf ()
sumOf (42, 597, 12)
Next time to write the function, a lot of T T

Swift Tour essay summary (4)