pragma mark 分类基本概念

pragma mark 概念

/**
 Category 有很多种说法: 分类、类别、类目 (一般情况下都叫分类)
 
 Category是OC特有的语法,其他语言没有的语言
 
 作用:
 可以在不修改原来 类 的基础上, 为这个类扩充一些方法
 一个庞大的类 可以分模块开发  (人有体育运动、日常生活的方法 可以拆分2个类)
 一个庞大的类 可以由多个人来编写, 更利于团队合作
 */
 

pragma mark 代码

#import <Foundation/Foundation.h>
#pragma mark 类
#import "Person.h"

#pragma mark 分类
#import "Person+LYH.h"
#pragma mark main函数

/**
 方法:
 方法的声明:
 方法的实现:
 
 所以通过分类给某一个类扩充方法, 也分为 声明和实现 两个部分
 
 
 #warning 分类的声明
 @interface ClassName (CategoryName)
 NewMethod; // 在类别中添加方法
 // 不允许在类别添加变量
  @end
 
 ClassName      : 需要给那个类扩张方法
 CategoryName   : 分类的名称
 NewMethod      : 扩充的方法
 
 #warning 分类的实现
 @implementation ClassName (CategoryName)
 NewMethod
 ... ...
 @end
 
 ClassName      : 需要给那个类扩张方法
 CategoryName   : 分类的名称
 NewMethod      : 扩充的方法
 */
int main(int argc, const char * argv[])
{
    Person *p = [[Person alloc]init];
    p.age = 30;
    [p say];
    [p playFootball];
    [p playBasketBall];
    
#warning 在不修改类的情况下, 为类添加方法 可以有两种方法: 一、继承 。二、分类Category
    
//    NSString;
#warning 1.系统的NSString 的基本方法
//     @interface NSString : NSObject <NSCopying, NSMutableCopying, NSSecureCoding>
//     
//     #pragma mark *** String funnel methods ***
//     
//     /* NSString primitives. A minimal subclass of NSString just needs to implement these two, along with an init method appropriate for that subclass. We also recommend overriding getCharacters:range: for performance.
//     */
//    @property (readonly) NSUInteger length;
//    - (unichar)characterAtIndex:(NSUInteger)index;
//    
//    /* The initializers available to subclasses. See further below for additional init methods.
//     */
//    - (instancetype)init NS_DESIGNATED_INITIALIZER;
//    - (nullable instancetype)initWithCoder:(NSCoder *)aDecoder NS_DESIGNATED_INITIALIZER;
//    
//    @end
    
     
#warning  2.系统的 NSString 扩充的方法
//     @interface NSString (NSStringExtensionMethods)
    
    
    NSArray;
#warning 1.系统的NSArray基础的方法
    /*
     @interface NSArray<__covariant ObjectType> : NSObject <NSCopying, NSMutableCopying, NSSecureCoding, NSFastEnumeration>
     
     @property (readonly) NSUInteger count;
     - (ObjectType)objectAtIndex:(NSUInteger)index;
     - (instancetype)init NS_DESIGNATED_INITIALIZER;
     - (instancetype)initWithObjects:(const ObjectType [])objects count:(NSUInteger)cnt NS_DESIGNATED_INITIALIZER;
     - (nullable instancetype)initWithCoder:(NSCoder *)aDecoder NS_DESIGNATED_INITIALIZER;
     
     @end
     */
#warning 1.系统的NSArray扩充的方法
    /**
     @interface NSArray<ObjectType> (NSExtendedArray)
     
     - (NSArray<ObjectType> *)arrayByAddingObject:(ObjectType)anObject;
     - (NSArray<ObjectType> *)arrayByAddingObjectsFromArray:(NSArray<ObjectType> *)otherArray;
     - (NSString *)componentsJoinedByString:(NSString *)separator;
     - (BOOL)containsObject:(ObjectType)anObject;
     @property (readonly, copy) NSString *description;
     - (NSString *)descriptionWithLocale:(nullable id)locale;
     - (NSString *)descriptionWithLocale:(nullable id)locale indent:(NSUInteger)level;
     - (nullable ObjectType)firstObjectCommonWithArray:(NSArray<ObjectType> *)otherArray;
     - (void)getObjects:(ObjectType __unsafe_unretained [])objects range:(NSRange)range;
     - (NSUInteger)indexOfObject:(ObjectType)anObject;
     - (NSUInteger)indexOfObject:(ObjectType)anObject inRange:(NSRange)range;
     - (NSUInteger)indexOfObjectIdenticalTo:(ObjectType)anObject;
     - (NSUInteger)indexOfObjectIdenticalTo:(ObjectType)anObject inRange:(NSRange)range;
     - (BOOL)isEqualToArray:(NSArray<ObjectType> *)otherArray;
     @property (nullable, nonatomic, readonly) ObjectType firstObject NS_AVAILABLE(10_6, 4_0);
     @property (nullable, nonatomic, readonly) ObjectType lastObject;
     - (NSEnumerator<ObjectType> *)objectEnumerator;
     - (NSEnumerator<ObjectType> *)reverseObjectEnumerator;
     @property (readonly, copy) NSData *sortedArrayHint;
     - (NSArray<ObjectType> *)sortedArrayUsingFunction:(NSInteger (*)(ObjectType, ObjectType, void * __nullable))comparator context:(nullable void *)context;
     - (NSArray<ObjectType> *)sortedArrayUsingFunction:(NSInteger (*)(ObjectType, ObjectType, void * __nullable))comparator context:(nullable void *)context hint:(nullable NSData *)hint;
     - (NSArray<ObjectType> *)sortedArrayUsingSelector:(SEL)comparator;
     - (NSArray<ObjectType> *)subarrayWithRange:(NSRange)range;
     - (BOOL)writeToFile:(NSString *)path atomically:(BOOL)useAuxiliaryFile;
     - (BOOL)writeToURL:(NSURL *)url atomically:(BOOL)atomically;
     
     - (void)makeObjectsPerformSelector:(SEL)aSelector NS_SWIFT_UNAVAILABLE("Use enumerateObjectsUsingBlock: or a for loop instead");
     - (void)makeObjectsPerformSelector:(SEL)aSelector withObject:(nullable id)argument NS_SWIFT_UNAVAILABLE("Use enumerateObjectsUsingBlock: or a for loop instead");
     
     - (NSArray<ObjectType> *)objectsAtIndexes:(NSIndexSet *)indexes;
     
     - (ObjectType)objectAtIndexedSubscript:(NSUInteger)idx NS_AVAILABLE(10_8, 6_0);
     
     - (void)enumerateObjectsUsingBlock:(void (^)(ObjectType obj, NSUInteger idx, BOOL *stop))block NS_AVAILABLE(10_6, 4_0);
     - (void)enumerateObjectsWithOptions:(NSEnumerationOptions)opts usingBlock:(void (^)(ObjectType obj, NSUInteger idx, BOOL *stop))block NS_AVAILABLE(10_6, 4_0);
     - (void)enumerateObjectsAtIndexes:(NSIndexSet *)s options:(NSEnumerationOptions)opts usingBlock:(void (^)(ObjectType obj, NSUInteger idx, BOOL *stop))block NS_AVAILABLE(10_6, 4_0);
     
     - (NSUInteger)indexOfObjectPassingTest:(BOOL (^)(ObjectType obj, NSUInteger idx, BOOL *stop))predicate NS_AVAILABLE(10_6, 4_0);
     - (NSUInteger)indexOfObjectWithOptions:(NSEnumerationOptions)opts passingTest:(BOOL (^)(ObjectType obj, NSUInteger idx, BOOL *stop))predicate NS_AVAILABLE(10_6, 4_0);
     - (NSUInteger)indexOfObjectAtIndexes:(NSIndexSet *)s options:(NSEnumerationOptions)opts passingTest:(BOOL (^)(ObjectType obj, NSUInteger idx, BOOL *stop))predicate NS_AVAILABLE(10_6, 4_0);
     
     - (NSIndexSet *)indexesOfObjectsPassingTest:(BOOL (^)(ObjectType obj, NSUInteger idx, BOOL *stop))predicate NS_AVAILABLE(10_6, 4_0);
     - (NSIndexSet *)indexesOfObjectsWithOptions:(NSEnumerationOptions)opts passingTest:(BOOL (^)(ObjectType obj, NSUInteger idx, BOOL *stop))predicate NS_AVAILABLE(10_6, 4_0);
     - (NSIndexSet *)indexesOfObjectsAtIndexes:(NSIndexSet *)s options:(NSEnumerationOptions)opts passingTest:(BOOL (^)(ObjectType obj, NSUInteger idx, BOOL *stop))predicate NS_AVAILABLE(10_6, 4_0);
     
     - (NSArray<ObjectType> *)sortedArrayUsingComparator:(NSComparator)cmptr NS_AVAILABLE(10_6, 4_0);
     - (NSArray<ObjectType> *)sortedArrayWithOptions:(NSSortOptions)opts usingComparator:(NSComparator)cmptr NS_AVAILABLE(10_6, 4_0);
     
     typedef NS_OPTIONS(NSUInteger, NSBinarySearchingOptions) {
     NSBinarySearchingFirstEqual = (1UL << 8),
     NSBinarySearchingLastEqual = (1UL << 9),
     NSBinarySearchingInsertionIndex = (1UL << 10),
     };
     
     - (NSUInteger)indexOfObject:(ObjectType)obj inSortedRange:(NSRange)r options:(NSBinarySearchingOptions)opts usingComparator:(NSComparator)cmp NS_AVAILABLE(10_6, 4_0); // binary search
     
     @end
     */
    return 0;
}

Person+LYH.h //分类的名称

#import "Person.h"

// 此处的Person 的名字 一定要和 扩充类的那个名字 一样
@interface Person (LYH)
// 扩充方法
- (void)playFootball;

- (void)playBasketBall;
@end

Person+LYH.m

#import "Person+LYH.h"

@implementation Person (LYH)
// 实现扩充方法
- (void)playFootball
{
    NSLog(@"%s",__func__);
}

- (void)playBasketBall
{
    NSLog(@"%s",__func__);
}
@end

---

Person.h //人类

#import <Foundation/Foundation.h>

@interface Person : NSObject

@property (nonatomic,assign)int age;

- (void)say;
@end

Person.m

#import "Person.h"

@implementation Person

- (void)say
{
    NSLog(@"age = %i",_age);
}
@end

---