ios - 如何在 Swift 中的 UILabel 上显示 Float 值？

Question

import UIKit

class ViewController: UIViewController {
@IBOutlet weak var Screen: UILabel!
var firstNumber = Float()
var secondNumber = Float()
var result = Float()
var operation = ""
var isTypingNumber = false
@IBAction func Number(sender: AnyObject) {
    isTypingNumber = false
    var number = sender.currentTitle
    if isTypingNumber == true {
        Screen.text = Screen.text! + number!!;
    } else {
        Screen.text = number!!;
    }
    isTypingNumber = true
}
@IBAction func Operation(sender: AnyObject) {
    operation = sender.currentTitle!!
    isTypingNumber = false
    firstNumber = Screen.text!.toInt()!
}
@IBAction func Equals(sender: AnyObject) {
    secondNumber = Screen.text!.toInt()!
    isTypingNumber = false
    if operation == "+" {
        result = firstNumber + secondNumber;
    } else if operation == "-" {
        result = firstNumber - secondNumber;
    } else if operation == "x" {
        result = firstNumber * secondNumber;
    } else if operation == "/" {
        result = firstNumber / secondNumber;
    }
    Screen.text = "\(result)"
}
@IBAction func Clear(sender: AnyObject) {
    firstNumber = 0
    secondNumber = 0
    result = 0
    Screen.text = "\(result)"
}
override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.
}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}


}

这是我的代码。我总是在 firstNumber = Screen.text!.toInt() 上收到错误“Int”无法转换为“Float”!和 secondNumber = Screen.text!.toInt()!
我正在尝试在 UILabel(Screen) 上显示一个 float 。我该怎么做？谁能告诉我如何在 UILabel 中使用 float 。这是 swift 。

谢谢，罗希特

Answer 1

您正在尝试将 Int 值分配给 Float 类型的变量。这在 swift 中是不允许的。你可以试试

let floatValue = (label.text as NSString).floatValue

要在 UILabel 中显示 floatValue，您可以在 swift 中使用字符串插值。

label.text = "\(floatValue)"

要将 Int 转换为 Float，您可以这样做

floatValue = Float(intValue)