给String写一个分类,对外提供一个方法,判断输入数字是否>0
extension String {
func enteredCorrectly() -> Bool {
if characters.count == 0 {
return false
}
let scan = Scanner(string: self)
let isNotZero = Double(self)
guard let isNum = isNotZero else {
return false
}
if isNum > 0 {
if contains(".") {
if let rangeOfZero = range(of: ".", options: .backwards) {
let suffix = String(characters.suffix(from: rangeOfZero.lowerBound))
if (suffix.characters.count > 2) {
// showAlert(controller, message: "您输入的金额有误")
return false
}
}
var float: Float = 0
guard !(scan.scanFloat(&float) && scan.isAtEnd) else { return true }
} else {
var int: Int64 = 0
guard !(scan.scanInt64(&int) && scan.isAtEnd) else { return true }
}
}
return false
}
}
