如何在Swift中检查字符串是否包含中文?

时间:2015-07-06 11:11:50

标签: swift chinese-locale

我想知道如何在Swift中检查字符串是否包含中文?

例如,我想检查里面是否有中文:

{{1}}

谢谢!

5 个答案:

答案 0 :(得分:9)

This answer How to determine if a character is a Chinese character也可轻松翻译成{{3}} Ruby to Swift(现在更新为Swift 3):

extension String {
    var containsChineseCharacters: Bool {
        return self.range(of: "\\p{Han}", options: .regularExpression) != nil
    }
}

if myString.containsChineseCharacters {
    print("Contains Chinese")
}

在正则表达式中,“\ p {Han}”匹配所有字符 “Han”Unicode属性,正如我所理解的那样 - 是角色 来自CJK语言。

答案 1 :(得分:5)

查看有关如何在其他语言中执行此操作的问题(例如Ruby的this accepted answer),看起来常见的技术是确定字符串中的每个字符是否都在CJK范围内。 ruby的答案可以通过以下代码适应Swift字符串作为扩展名:

extension String {
    var containsChineseCharacters: Bool {
        return self.unicodeScalars.contains { scalar in
            let cjkRanges: [ClosedInterval<UInt32>] = [
                0x4E00...0x9FFF,   // main block
                0x3400...0x4DBF,   // extended block A
                0x20000...0x2A6DF, // extended block B
                0x2A700...0x2B73F, // extended block C
            ]
            return cjkRanges.contains { $0.contains(scalar.value) }
        }
    }
}

// true:
"Hi! 大家好!It's contains Chinese!".containsChineseCharacters
// false:
"Hello, world!".containsChineseCharacters

这些范围可能已存在于Foundation的某处,而不是手动对其进行硬编码。

以上是针对Swift 2.0的,对于之前的版本,您必须使用免费的contains函数而不是协议扩展(两次):

extension String {
    var containsChineseCharacters: Bool {
        return contains(self.unicodeScalars) {
          // older version of compiler seems to need extra help with type inference 
          (scalar: UnicodeScalar)->Bool in
            let cjkRanges: [ClosedInterval<UInt32>] = [
                0x4E00...0x9FFF,   // main block
                0x3400...0x4DBF,   // extended block A
                0x20000...0x2A6DF, // extended block B
                0x2A700...0x2B73F, // extended block C
            ]
            return contains(cjkRanges) { $0.contains(scalar.value) }
        }
    }
}

答案 2 :(得分:2)

在Swift 2中试试这个:

var myString = "Hi! 大家好!It's contains Chinese!"

var a = false

for c in myString.characters {
    let cs = String(c)
    a = a || (cs != cs.stringByApplyingTransform(NSStringTransformMandarinToLatin, reverse: false))
}
print("\(myString) contains Chinese characters = \(a)")

答案 3 :(得分:1)

接受的答案只能找到字符串是否包含中文字符,我为自己的情况创建了一个套装:

enum ChineseRange {
    case notFound, contain, all
}

extension String {
    var findChineseCharacters: ChineseRange {
        guard let a = self.range(of: "\\p{Han}*\\p{Han}", options: .regularExpression) else {
            return .notFound
        }
        var result: ChineseRange
        switch a {
        case nil:
            result = .notFound
        case self.startIndex..<self.endIndex:
            result = .all
        default:
            result = .contain
        }
        return result
    }
}

if "你好".findChineseCharacters == .all {
    print("All Chinese")
}

if "Chinese".findChineseCharacters == .notFound {
    print("Not found Chinese")
}

if "Chinese你好".findChineseCharacters == .contain {
    print("Contains Chinese")
}

请点击此处:https://gist.github.com/williamhqs/6899691b5a26272550578601bee17f1a

答案 4 :(得分:0)

我创建了一个Swift 3 String扩展,用于检查String包含的中文字符数。类似于Airspeed Velocity的代码,但更全面。检查各种Unicode范围以查看字符是否为中文。请参阅Unicode标准规范中第18.1节表格中列出的中文字符范围:http://www.unicode.org/versions/Unicode9.0.0/ch18.pdf

可以在GitHub上找到String扩展名:https://github.com/niklasberglund/String-chinese.swift

用法示例:

let myString = "Hi! 大家好!It contains Chinese!"
let chinesePercentage = myString.chinesePercentage()
let chineseCharacterCount = myString.chineseCharactersCount()
print("String contains \(chinesePercentage) percent Chinese. That's \(chineseCharacterCount) characters.")