Swift 5:不推荐使用String.UTF16View.Index(encodedOffset:l)

时间:2019-03-27 13:35:02

标签: swift swift5

我正在使用此代码在字符串中插入连字符以更好地换行。使用Swift 5,我得到的信息

  

String.UTF16View.Index(encodedOffset:l)

将不推荐使用。但是我找不到正确的参数。有什么想法吗?

import Foundation

extension String {

    func hyphenated(languageCode: String) -> String {
        let locale = Locale(identifier: languageCode)
        return self.hyphenated(locale: locale)
    }

    func hyphenated(locale: Locale) -> String {
        guard CFStringIsHyphenationAvailableForLocale(locale as CFLocale) else { return self }

        var s = self

        let fullRange = CFRangeMake(0, s.utf16.count)
        var hyphenationLocations = [CFIndex]()
        for (i, _) in s.utf16.enumerated() {
            let location: CFIndex = CFStringGetHyphenationLocationBeforeIndex(s as CFString, i, fullRange, 0, locale as CFLocale, nil)
            if hyphenationLocations.last != location {
                hyphenationLocations.append(location)
            }
        }

        for l in hyphenationLocations.reversed() {
            guard l > 0 else { continue }
            let strIndex = String.UTF16View.Index(encodedOffset: l)
            // insert soft hyphen:
            s.insert("\u{00AD}", at: strIndex)
            // or insert a regular hyphen to debug:
            // s.insert("-", at: strIndex)
        }

        return s
    }
}

1 个答案:

答案 0 :(得分:3)

l是字符串s中以UTF-16代码为单位的偏移量,因此您可以替换

let strIndex = String.UTF16View.Index(encodedOffset: l)

作者

let strIndex = s.utf16.index(s.utf16.startIndex, offsetBy: l)

或使用

let strIndex = String.Index(utf16Offset: l, in: s)

它是由Swift 5中的SE-0241 Deprecate String Index Encoded Offsets引入的。