swift - lyricsForName 函数不打印任何内容

Question

lyricsForName 函数不打印任何内容。 shortNameFromName 确实有效，我已经检查了第二个函数有什么问题。

func shortNameFromName(name : String) ->String{
    var shortName = ""

    let lowercaseNmae = name.lowercased()
    let vowelSet = CharacterSet(charactersIn: "aeiou")
    if let range = lowercaseNmae.rangeOfCharacter(from: vowelSet, options: String.CompareOptions.caseInsensitive)
    {
        shortName = name.substring(from: range.lowerBound)
    }

    return shortName
}

func lyricsForName(lyricsTemplate : String , fullName : String) ->String{
    let bananaFanaTemplate = ["<FULL_NAME>, <FULL_NAME>, Bo B<SHORT_NAME",
                            "Banana Fana Fo F<SHORT_NAME>",
                             "Me My Mo M<SHORT_NAME>",
                             "<FULL_NAME>"].joined(separator: "\n")
    let shortName = shortNameFromName(name: fullName)
    let lyrics = lyricsTemplate
        .replacingOccurrences(of: "<FULL_NAME>", with: fullName)
        .replacingOccurrences(of: "<SHORT_NAME>", with: shortName)

    print(lyricsForName(lyricsTemplate:bananaFanaTemplate , fullName: "vishnu"))

    return lyrics
}

第一个功能完美运行，但我猜第二个功能无法正常运行。我应该怎么做才能让它发挥作用？

Answer 1

我现在在办公 table 旁，所以快速浏览了您的代码。这现在有效(注意 bananaFanaTemplate 中的拼写错误):

func shortNameFromName(name : String) ->String{
     var shortName = ""

     let lowercaseNmae = name.lowercased()
     let vowelSet = CharacterSet(charactersIn: "aeiou")
     if let range = lowercaseNmae.rangeOfCharacter(from: vowelSet, options: String.CompareOptions.caseInsensitive) {
          shortName = name.substring(from: range.lowerBound)
     }

     return shortName
 }

 func lyricsForName(lyricsTemplate : String , fullName : String) -> String {

     let shortName = shortNameFromName(name: fullName)
     let lyrics = lyricsTemplate
          .replacingOccurrences(of: "<FULL_NAME>", with: fullName)
          .replacingOccurrences(of: "<SHORT_NAME>", with: shortName)

     print(lyrics)

     return lyrics
 }

 let bananaFanaTemplate : String = ["<FULL_NAME>, <FULL_NAME>, Bo B<SHORT_NAME>",
                               "Banana Fana Fo F<SHORT_NAME>",
                               "Me My Mo M<SHORT_NAME>",
                               "<FULL_NAME>"].joined(separator: "\n")

 print(lyricsForName(lyricsTemplate:bananaFanaTemplate , fullName: "vishnu"))

输出:

毗湿奴，毗湿奴，博比什努 香蕉法纳佛 Fishnu 我我的莫米什努 毗湿奴

我认为您对函数作用域问题很困惑。您在函数的实现中声明了常量 bananaFanaTemplate，该参数应该已传递给函数。同样，您从函数体内调用函数，通常不会这样做，除非它应该是递归函数。

看看:https://developer.apple.com/library/content/documentation/Swift/Conceptual/Swift_Programming_Language/Functions.html

希望对您有所帮助。