Question

考虑到用户区域设置，如何将段落中每个句子的第一个单词大写？我想要实现的是无论句子里面的情况如何，每个单词的第一个字母都是大写的，其余的都是小写的。首先将所有内容转换为小写，然后获得第一个字母并制作大写字母，最后将它们加在一起，我只能做一个句子。我的问题与How to capitalize each word in a string using Swift iOS不同，因为我不想将每个单词都大写。我只想把每个句子的第一个单词弄清楚。 capitalizedString转

"this is first sentence. this is second sentence."

到

"This Is First Sentence. This Is Second Sentence."

我想要的是

"This is first sentence. This is second sentence."

我的问题也与Capitalise first letter of every sentence不同，因为@ rintaro的代码不适用于我的下面的例子。它保留原始文本中的大写字母完整。使用@ rintaro的代码;

前

"someSentenceWith UTF text İŞğĞ. anotherSentenceğüÜğ"

后

"SomeSentenceWith UTF text İŞğĞ. AnotherSentenceğüÜğ."

我想要实现的目标，

"Somesentencewith utf text işğğ. Anothersentenceğüüğ."

我的代码只能进行部分转换。

var description = "someSentenceWith UTF text İŞğĞ. anotherSentenceğüÜğ"
description = description.lowercaseStringWithLocale(NSLocale.currentLocale())
let first = description.startIndex
let rest = advance(first,1)..<description.endIndex
let capitalised = description[first...first].uppercaseStringWithLocale(NSLocale.currentLocale()) + description[rest]

如果您能仔细阅读我的问题，我将非常感谢，因为这是我第三次编辑这个问题。如果我不能清楚地问清楚，我真的很抱歉，因为我不是母语人士。所以尽管@rintaro回答了类似的问题，但他的答案并没有解决我的问题。 @ martin-r提出了一个Objective-C答案，它再次解决了我的问题。有另一个用户埃里克的东西，他们也提出了另一个答案，但事后删除。我只是无法理解为什么有几个人提出了不回答我的问题的不同答案。

Answer 1

尝试：

let str = "someSentenceWith UTF text İŞğĞ. anotherSentenceğüÜğ"

var result = ""
str.uppercaseString.enumerateSubstringsInRange(indices(str), options: .BySentences) { (sub, _, _, _)  in
    result += sub[sub.startIndex ... sub.startIndex]
    result += sub[sub.startIndex.successor() ..< sub.endIndex].lowercaseString
}

println(result) // -> "Somesentencewith utf text i̇şğğ. Anothersentenceğüüğ"

ADDED：Swift2

let str = "someSentenceWith UTF text İŞğĞ. anotherSentenceğüÜğ"

var result = ""
str.uppercaseString.enumerateSubstringsInRange(str.characters.indices, options: .BySentences) { (sub, _, _, _)  in
    result += String(sub!.characters.prefix(1))
    result += String(sub!.characters.dropFirst(1)).lowercaseString
}

print(result)

Answer 2

更新@ rintaro的Swift 3代码：

let str = "someSentenceWith UTF text İŞğĞ. anotherSentenceğüÜğ"

var result = ""
str.uppercased().enumerateSubstrings(in: str.startIndex..<str.endIndex, options: .bySentences) { (sub, _, _, _)  in
    result += String(sub!.characters.prefix(1))
    result += String(sub!.characters.dropFirst(1)).lowercased()
}

print(result)

Answer 3

您可以使用正则表达式来实现此目的。我将此函数添加为字符串扩展名，因此将来调用将是微不足道的：

extension String {

    func toUppercaseAtSentenceBoundary() -> String {
        var string = self.lowercaseString

        var capacity = string.utf16Count
        var mutable = NSMutableString(capacity: capacity)
        mutable.appendString(string)

        var error: NSError?

        if let regex = NSRegularExpression(
            pattern: "(?:^|\\b\\.[ ]*)(\\p{Ll})",
            options: NSRegularExpressionOptions.AnchorsMatchLines,
            error: &error
            ) {

            if let results = regex.matchesInString(
                string,
                options: NSMatchingOptions.allZeros,
                range: NSMakeRange(0, capacity)
                ) as? [NSTextCheckingResult] {

                    for result in results {
                        let numRanges = result.numberOfRanges
                        if numRanges >= 1 {
                            for i in 1..<numRanges {
                                let range = result.rangeAtIndex(i)
                                let substring = mutable.substringWithRange(range)
                                mutable.replaceCharactersInRange(range, withString: substring.uppercaseString)
                            }
                        }
                    }
            }
        }

        return mutable
    }
}

var string = "someSentenceWith UTF text İŞğĞ. anotherSentenceğüÜğ.".toUppercaseAtSentenceBoundary()

Answer 4

我根据@ Katy的代码

在Swift 3中写了这个扩展名

extension String {

func toUppercaseAtSentenceBoundary() -> String {

 var result = ""
    self.uppercased().enumerateSubstrings(in: self.startIndex..<self.endIndex, options: .bySentences) { (sub, _, _, _)  in
        result += String(sub!.characters.prefix(1))
        result += String(sub!.characters.dropFirst(1)).lowercased()
    }

    return result as String 
  }
}

使用方法：

let string = "This is First sentence. This is second Sentence.".toUppercaseAtSentenceBoundary() 
print(string) /* Output: "This is first sentence. This is second sentence." */

如何使用Swift将每个句子中的第一个单词大写

4 个答案: