Question

所以我对Swift相当新（试图自学），而且我已经陷入困境。我试图创建一个函数，接受一个字符串作为参数，检查第一个元音之前是否有任何辅音，如果是的话，删除它。因此，如果用户输入他的名字作为Michael，那么ichael会打印出来。我写了

func shortNameForName(name: String) -> String {

    let shortName = name.lowercaseString
    let vowelSet = CharacterSet(charactersIn: "aeiou")

    /* I know here i can create an if statement that basically states that if the first
       character of the string does not contain the vowelset, remove it, but I don't know
       the syntax/how to write it */

    return shortName
}

print(shortNameForName("Michael"))

Answer 1

你可以这样做。

func shortNameForName(name: String) -> String {

    let charSet = CharacterSet(charactersIn: "aeiou")

    if let index = name.lowercased().rangeOfCharacter(from: charSet)?.lowerBound {
        return name.substring(from: index)
    }

    return ""
}

shortNameForName(name: "Michael")

Answer 2

使用Swift 3和正则表达式的简单解决方案：

 $sql = "SELECT s.*, u.avatar
        FROM status AS s
        LEFT JOIN users AS u ON u.username = s.author
        WHERE s.author IN ('$friendsCSV') AND (s.data LIKE '%#$tag%') AND (s.type='a' OR s.type='c' OR s.type='d')
        ORDER BY s.postdate DESC LIMIT 20";

Answer 3

Swift 3

试试这个

func shortName(for name: String) -> String {
    // regular expression for consonants (= not vowels) in the beginning
    let regularExpression = "^[^aeiou]+"

    guard let firstVowelRange = name.range(
        of: regularExpression,
        options: [.caseInsensitive, .regularExpression],
        range: nil
    ) else {
        return name
    }

    // if the reg exp matched something, remove it
    return name.substring(from: firstVowelRange.upperBound)
}

print(shortName(for: "Michael"))
print(shortName(for: "MMMichael"))

PS：未经测试

Answer 4

您可以使用NSRegularExpression编写类似的内容：

func shortNameForName(name: String) -> String {

    let pattern = "^[^aeiou]+([aeiou])"
    let regex = try! NSRegularExpression(pattern: pattern, options: .caseInsensitive)
    let shortName = regex.stringByReplacingMatches(in: name, range: NSRange(0..<name.utf16.count), withTemplate: "$1")
    return shortName //or `shortName.lowercased()` if you prefer
}

print(shortNameForName(name: "Michael")) //->ichael

Answer 5

Swift 4

func shortNameFromName(_ name: String) -> String {
    let lowercaseName = name.lowercased()
    let vowelSet = CharacterSet(charactersIn: "aeiou")

    if let index = lowercaseName.rangeOfCharacter(from: vowelSet)?.lowerBound {
        return String(lowercaseName[index...])
    } else {
        return lowercaseName
    }
}

如何编写一个函数，它接受一个字符串并删除第一个元音之前的任何辅音

5 个答案: