swift - 如何在 Swift 中将字符串 "\u{0026}"转换为 "&"？

Question

我有一个可以包含“\u{0026}”形式的 unicode 字符的字符串，我希望将其转换为适当的字符“&”。

我该怎么做？

let input = "\\u{0026} something else here"
let expectedOutput = "& something else here"

非常感谢!

Answer 1

您可能需要使用正则表达式:

class StringEscpingRegex: NSRegularExpression {
    override func replacementString(for result: NSTextCheckingResult, in string: String, offset: Int, template templ: String) -> String {
        let nsString = string as NSString
        if
            result.numberOfRanges == 2,
            case let capturedString = nsString.substring(with: result.rangeAt(1)),
            let codePoint = UInt32(capturedString, radix: 16),
            codePoint != 0xFFFE, codePoint != 0xFFFF, codePoint <= 0x10FFFF,
            codePoint<0xD800 || codePoint > 0xDFFF
        {
            return String(Character(UnicodeScalar(codePoint)!))
        } else {
            return super.replacementString(for: result, in: string, offset: offset, template: templ)
        }
    }
}

let pattern = "\\\\u\\{([0-9A-Fa-f]{1,6})\\}"
let regex = try! StringEscpingRegex(pattern: pattern)

let input = "\\u{0026} something else here"
let expectedOutput = "& something else here"

let actualOutput = regex.stringByReplacingMatches(in: input, range: NSRange(0..<input.utf16.count), withTemplate: "?")

assert(actualOutput == expectedOutput) //assertion succeeds

<小时/>

我不明白您是如何获得输入的。但如果您采用某种基于标准的表示形式，则可以更简单地获得 expectedOutput。