swift removingPercentEncoding not work with a gb2312 string

问题:

The server returns a gb2312 string that has been processed by the urlencode function:

%D7%CF%BD%FB%B3%C7%C4%A7%D6%E4_%CE%DE%CF%DE%D0%A1%CB%B5%CD%F8_www.55x.cn.rar

How to decode it back to gb2312 string:

紫禁城魔咒_无限小说网_www.55x.cn.rar

回答1:

Percent encoding on other encodings than UTF-8 is not considered to be a recommended way in recent www world, so you may need to implement such conversion by yourself.

It may be something like this:

extension String.Encoding {     static let gb_18030_2000 = String.Encoding(rawValue: CFStringConvertEncodingToNSStringEncoding(CFStringEncoding(CFStringEncodings.GB_18030_2000.rawValue))) }  extension String {     func bytesByRemovingPercentEncoding(using encoding: String.Encoding) -> Data {         struct My {             static let regex = try! NSRegularExpression(pattern: "(%[0-9A-F]{2})|(.)", options: .caseInsensitive)         }         var bytes = Data()         let nsSelf = self as NSString         for match in My.regex.matches(in: self, range: NSRange(0..<self.utf16.count)) {             if match.rangeAt(1).location != NSNotFound {                 let hexString = nsSelf.substring(with: NSMakeRange(match.rangeAt(1).location+1, 2))                 bytes.append(UInt8(hexString, radix: 16)!)             } else {                 let singleChar = nsSelf.substring(with: match.rangeAt(2))                 bytes.append(singleChar.data(using: encoding) ?? "?".data(using: .ascii)!)             }         }         return bytes     }     func removingPercentEncoding(using encoding: String.Encoding) -> String? {         return String(data: bytesByRemovingPercentEncoding(using: encoding), encoding: encoding)     } }  let origStr = "%D7%CF%BD%FB%B3%C7%C4%A7%D6%E4_%CE%DE%CF%DE%D0%A1%CB%B5%CD%F8_www.55x.cn.rar" print(origStr.removingPercentEncoding(using: .gb_18030_2000)) //->Optional("紫禁城魔咒_无限小说网_www.55x.cn.rar") 

文章来源: swift removingPercentEncoding not work with a gb2312 string