如何在Swift中将浮点数显示在UILabel上？

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。我一直收到错误提示“Int”无法转换为“Float”，在firstNumber = Screen.text！.toInt（）！和secondNumber = Screen.text！.toInt（）！上。
我试图在UILabel（Screen）上显示浮点数。我应该怎么做？ 有人能告诉我如何在UILabel中使用float，这是Swift。

谢谢， Rohit

- Rohorao

---

您已经在标签中显示了浮点值。您不应该尝试从标签中提取浮点值；您应该在数据中保留浮点值。标签只是一个视图；浮点值才是模型。 - matt

Answer 1

您正在尝试将一个Int值赋给类型为Float的变量。在Swift中，这是不允许的。您可以尝试使用以下方法：

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)"

要将一个 Int 转换为 Float，您可以执行以下操作：

floatValue = Float(intValue)

- rakeshbs

Answer 2

问题在于您将firstNumber声明为Float类型，但是您正在向该变量分配一个Int值。

更改为：

firstNumber = Screen.text!.toInt()!

to

firstNumber = (Screen.text! as NSString).floatValue

注意：同样适用于secondNumber。

- Midhun MP

---

对我有用。谢谢！ - Rohorao

Answer 3

你可以尝试这个：

你可以尝试这个：

@IBAction var label:UILabel!
var a:Float=1938.22

override func viewDidLoad(){
   super.viewDidLoad()
   label.text="\(a)"
}

- Dhruv Ramani