见的NSCharacterSet（SWIFT）字符

Question

当我试图列出字符的NSCharacterSet这样

print(NSCharacterSet.URLQueryAllowedCharacterSet()) 

未打印出来的人物，而是类似的东西来

< __NSCFCharacterSet ：0x1759b900>

Answer 1

基于another answer，这里是在夫特派生吸尘器版本2.0/3.0：

extension NSCharacterSet { 
    var characters:[String] { 
     var chars = [String]() 
     for plane:UInt8 in 0...16 { 
      if self.hasMemberInPlane(plane) { 
      let p0 = UInt32(plane) << 16 
      let p1 = (UInt32(plane) + 1) << 16 
      for c:UTF32Char in p0..<p1 { 
        if self.longCharacterIsMember(c) { 
         var c1 = c.littleEndian 
         let s = NSString(bytes: &c1, length: 4, encoding: NSUTF32LittleEndianStringEncoding)! 
         chars.append(String(s)) 
        } 
       } 
      } 
     } 
     return chars 
    } 
} 

用法：

let charset = NSCharacterSet.URLQueryAllowedCharacterSet() 
print(charset.characters.joinWithSeparator(""))