在 swift 5 中将货币文本字段转换为双倍?

Convert currency textfield to double in swift 5?

我有使用此 class 的货币文本字段。它工作正常(显示 1000000 -> 1,000,000)。如何从货币字符串转换回双精度值?请告诉我怎么做,非常感谢。

import UIKit

class CurrencyTextField: UITextField {
    var lastValue = 0
    let maxValue = 1_000_000_000_000_000_000
    var amount: Int {
        if let newValue = Int(string.digits), newValue < maxValue {
            lastValue = newValue
        } else if !hasText {
            lastValue = 0
        }
        return lastValue
    }
    override func didMoveToSuperview() {
        textAlignment = .right
        keyboardType = .numberPad
        text = Formatter.decimal.string(for: amount)
        addTarget(self, action: #selector(editingChanged), for: .editingChanged)
    }
    @objc func editingChanged(_ textField: UITextField) {
        text = Formatter.decimal.string(for: amount)
    }
}

extension NumberFormatter {
    convenience init(numberStyle: Style) {
        self.init()
        self.numberStyle = numberStyle
    }
}
struct Formatter {
    static let decimal = NumberFormatter(numberStyle: .decimal)
}
extension UITextField {
    var string: String { return text ?? "" }
}

extension String {
    private static var digitsPattern = UnicodeScalar("0")..."9"
    var digits: String {
        return unicodeScalars.filter { String.digitsPattern ~= [=11=] }.string
    }
}

extension Sequence where Iterator.Element == UnicodeScalar {
    var string: String { return String(String.UnicodeScalarView(self)) }
}

根据您在代码中显示的扩展,这应该可以将您的货币字符串转换为 Double 值:

let doubleValue = Double(yourCurrencyString.digits)

yourCurrencyString 替换为您保存货币字符串的任何变量。