swift - 将文本字段数据转换为十进制值并返回字符串

Question

我将文本字段字符串转换为 double 型以进行计算，然后返回字符串以将其输出在标签上。我现在正在处理货币输入，因此我需要将其转换为小数而不是 double 。有人可以帮忙吗？

func calcTotal() {
    let totalConv: Double? = Double(totalTextField.text!)
    let tipConv: Double? = Double(tipTextField.text!)
    guard totalConv != nil && tipConv != nil else {
        return
    }
    let result = totalConv! * ((tipConv! / 100) + 1)
    let output = String(format: "$ %.2f", result)
    totalAmount.text = String(output)
}

Answer 1

您只需要使用 Decimal(string:) 初始值设定项和 NumberFormatter (货币样式)来格式化您的十进制值。

func calcTotal() {
    guard
        let totalConv = Decimal(string: totalTextField.text!),
        let tipConv = Decimal(string: tipTextField.text!)
    else { return }
    let result = totalConv * ((tipConv / 100) + 1)
    totalAmount.text = Formatter.currency.string(for: result)
}

<小时/>

extension Formatter {
    static let currency: NumberFormatter = {
        let numberFormatter = NumberFormatter()
        numberFormatter.numberStyle = .currency
        return numberFormatter
    }()
}