Int轉換Float或Double:
let intVar : Int = 3
let doubleVar : Double = Double(intVar)
Int轉換爲String:
let intVar : Int = 3
let strVar : String = String(intVar)
String轉換爲Int:
let strVar : String = "123"
let intVar : Int? = strVar.toInt()
Double轉換爲String:
let doubleVar : Double = 3.14
let strVar : String = String(doubleVar)
Double保留兩位小數,需要對Double進行擴展:
extension Double {
func format(f: String) -> String {
return NSString(format: "%\(f)f", self)
}
}
let myDouble = 1.234567
println(myDouble.format(".2")
String轉換Double:
let strVar : String = "3.14"
var string = NSString(string: strVar)
string.doubleValue