Question

我想在UIViewController标签中插入一个变量字符：

e.g。 “Currency = $”当$是变量且可能 $，£，€取决于。

你是如何用这个来编程的？

Answer 1

你会这样做：

var letter = "$"
// You create a new uilabel named label
label.text = "Currency = " + letter

你想根据你的条件改变你的字母var。

以下是一个例子：

// var currency is a string used to
// read a paragraph 
 If(currency == "dollar") 
      letter = "$"
 Else if (currency == "British pound")
      letter = "£"
 Else if (currency == "yen")
      letter = "¥"
 ...

 label.text = "Currency = " + letter

以下是参考：strings and characters: Apple

希望这有帮助！

Answer 2

我认为最好的方法是为每个货币字符创建单独的变量，然后将它们附加到字符串中。然后，您可以将该标签的文本设置为该字符串。

let currencyCharacter:String = "$"
let viewControllerLabelText:String = "Currency = " + currencyCharacter
myViewControllerLabel.text = viewControllerLabelText

Answer 3

您可以通过将变量包装在\()中来使用字符串插值，如下所示：

let currency = "$"
currencyLabel.text = "Currency = \(currency)"

这会将该变量的值插入到周围的字符串中。在此处查看有关此主题的更多信息：https://developer.apple.com/library/ios/documentation/Swift/Conceptual/Swift_Programming_Language/StringsAndCharacters.html

Answer 4

这是一个干净的方法：

func currencySymbol(currency: String) -> String {
    switch currency {
        case "dollar": return "$"
        case "British pound": return "£"
        case "yen": return "¥"
        ///add others as needed
        default: return currency
    }
}

let string =  "Currency = \(currencySymbol("dollar"))"    //"Currency = $"

Swift：将变量插入标签？

4 个答案: