iOS复习笔记15:NSObject

@interface Student:NSObject
-(void)go;
-(void)showName:(NSString *)name;
-(void)introduce:(NSString *)name :(NSString*)address;
@end


Student* stu = [[Student alloc]init];

- (id)copyWithZone:(NSZone *)zone;
- (id)mutableCopyWithZone:(NSZone *)zone;

<pre name="code" class="objc">@interface Student:NSObject <NSCopying>
@end

@interface Student
(id)copyWithZone:(NSZone *)zone
{
	// 创建的副本对象不需要释放，有调用者释放
	// [self class]防止继承之后，返回父类对象
	Student* copy = [[[self class] allocWithZone:zone] init];


	return copy;
}
@end

// 相当于[stu go];
[stu performSelector:@selector(go)];
// 相当于[stu showName:@"Jun"];
[stu performSelector:@selector(showName:) withObjct:@"Jun"];
相当于[stu introduce:@"Jun":@"address"];
[stu performSelector:@selector(introduce::) withObjct:@"Jun" withObjct:@"address"];
// 延时2秒之后调用
[stu performSelector:@selector(showName:) withObjct:@"Jun" afterDelay:2];

// 字符串类名到类
NSString* className = @"Student";
Class class = NSClassFromString(className);
Person* p = [[class alloc] init];
// 类到字符串类名
NSString* strClass = NSStringFromClass([Person class]);

// 字符串方法名到方法
NSString* funName = @"go";
SEL selector = NSSelectorFromString(funName);
[stu performSelector:selector];
// 方法到字符串方法名
NSString* strFun = NSStringFromSelector(selector);

@interface NSObject <NSObject> {
        Class isa;
}

typedef struct objc_class *Class;

struct objc_class {
    Class isa;
};

- (BOOL)isMemberOfClass:(Class)cls {
    return [self class] == cls;
}


- (Class)class {
    return object_getClass(self);
}


Class object_getClass(id obj)
{
    return _object_getClass(obj);
}


static inline Class _object_getClass(id obj)
{
    if (obj) return obj->isa;
    else return Nil;
}

iOS复习笔记15:NSObject

原文：http://blog.csdn.net/xufeng0991/article/details/43534811