//NSCharacterSet其实是许多字符或者数字或者符号的组合,在网络处理的时候会用到
//Creating a Standard Character Set
+ (NSCharacterSet *)controlCharacterSet; //控制符
+ (NSCharacterSet *)whitespaceCharacterSet;//空格
+ (NSCharacterSet *)whitespaceAndNewlineCharacterSet;//空白&换行符
+ (NSCharacterSet *)decimalDigitCharacterSet; //小数
+ (NSCharacterSet *)letterCharacterSet; //文字
+ (NSCharacterSet *)lowercaseLetterCharacterSet;//小写字母
+ (NSCharacterSet *)uppercaseLetterCharacterSet;//大写字母
+ (NSCharacterSet *)nonBaseCharacterSet; //非基础字母
+ (NSCharacterSet *)alphanumericCharacterSet; //字母数字
+ (NSCharacterSet *)decomposableCharacterSet; //可分解
+ (NSCharacterSet *)illegalCharacterSet; //非法
+ (NSCharacterSet *)punctuationCharacterSet; //标点
+ (NSCharacterSet *)capitalizedLetterCharacterSet; //首字母大写
+ (NSCharacterSet *)symbolCharacterSet; //符号
+ (NSCharacterSet *)newlineCharacterSet NS_AVAILABLE(10_5, 2_0);//换行符
// Creating and Managing Character Sets as Bitmap Representations
//Returns a character set containing characters with Unicode values in a given range.
+ (NSCharacterSet *)characterSetWithRange:(NSRange)aRange;
// Returns a character set containing the characters in a given string.
+ (NSCharacterSet *)characterSetWithCharactersInString:(NSString *)aString;
//Returns a character set containing characters determined by a given bitmap representation.
+ (NSCharacterSet *)characterSetWithBitmapRepresentation:(NSData *)data;
+ (nullable NSCharacterSet *)characterSetWithContentsOfFile:(NSString *)fName;
//A character set containing only characters that don’t exist in the receiver. (read-only)
invertedSet
// Testing Set Membership
- (BOOL)characterIsMember:(unichar)aCharacter;
//Returns a Boolean value that indicates whether a given long character is a member of the receiver.
- (BOOL)longCharacterIsMember:(UTF32Char)theLongChar;
- (BOOL)isSupersetOfSet:(NSCharacterSet *)theOtherSet;
- (BOOL)hasMemberInPlane:(uint8_t)thePlane;
@end
@interface NSMutableCharacterSet : NSCharacterSet <NSCopying, NSMutableCopying>
- (void)addCharactersInRange:(NSRange)aRange;
- (void)removeCharactersInRange:(NSRange)aRange;
- (void)addCharactersInString:(NSString *)aString;
- (void)removeCharactersInString:(NSString *)aString;
- (void)formUnionWithCharacterSet:(NSCharacterSet *)otherSet;
- (void)formIntersectionWithCharacterSet:(NSCharacterSet *)otherSet;
- (void)invert;
+ (NSMutableCharacterSet *)controlCharacterSet;
+ (NSMutableCharacterSet *)whitespaceCharacterSet;
+ (NSMutableCharacterSet *)whitespaceAndNewlineCharacterSet;
+ (NSMutableCharacterSet *)decimalDigitCharacterSet;
+ (NSMutableCharacterSet *)letterCharacterSet;
+ (NSMutableCharacterSet *)lowercaseLetterCharacterSet;
+ (NSMutableCharacterSet *)uppercaseLetterCharacterSet;
+ (NSMutableCharacterSet *)nonBaseCharacterSet;
+ (NSMutableCharacterSet *)alphanumericCharacterSet;
+ (NSMutableCharacterSet *)decomposableCharacterSet;
+ (NSMutableCharacterSet *)illegalCharacterSet;
+ (NSMutableCharacterSet *)punctuationCharacterSet;
+ (NSMutableCharacterSet *)capitalizedLetterCharacterSet;
+ (NSMutableCharacterSet *)symbolCharacterSet;
+ (NSMutableCharacterSet *)newlineCharacterSet NS_AVAILABLE(10_5, 2_0);
+ (NSMutableCharacterSet *)characterSetWithRange:(NSRange)aRange;
+ (NSMutableCharacterSet *)characterSetWithCharactersInString:(NSString *)aString;
+ (NSMutableCharacterSet *)characterSetWithBitmapRepresentation:(NSData *)data;
+ (nullable NSMutableCharacterSet *)characterSetWithContentsOfFile:(NSString *)fName;