所以我非常擅长制作APP广告
Swift,我试图在文本字段中做一些非常简单的输入,取值,然后将它们用作Int进行某些计算.
但是’var distance’有些东西不正确
var handicapTal:Int
var MagicNumber:Int
var handicap = inputHCP.text.toInt()
var distance = inputDistance.text.toInt()
if (handicap >= 0 && handicap <= 20)
{
handicapTal = 30
}
else if(handicap > 20 && handicap <= 40){
handicapTal = 10
}
MagicNumber = distance - handicapTal
解决方法
在你的例子中,距离是一个Int？否则称为可选的Int. .toInt()返回Int？因为从String到Int的转换可能失败.请参阅以下示例：
Welcome to Swift! Type :help for assistance.
1> let a = "12"
a: String = "12"
2> let b = a.toInt()
b: Int? = 12
3> let c = "Hello"
c: String = "Hello"
4> let d = c.toInt()
d: Int? = nil
5> if let e = a.toInt() { println("e = \(e)") }
e = 12
6> if let f = c.toInt() { println("Huh?") }
7>
