oc之类排序

根据学生班级 ，姓名，年龄进行排序，若班级相同，则按照姓名进行排序

示例代码：

main.m

#import <Foundation/Foundation.h>
#import "Person.h"
#define NSLog(FORMAT, ...) printf("%s
", [[NSString stringWithFormat:FORMAT, ##__VA_ARGS__] UTF8String])

int main(int argc, const char * argv[]) {
    @autoreleasepool {
        Person *stu1=[[Person alloc]initClasses:@"IOS8"
                                        andName:@"ZXY"
                                        andAge:22];
        Person *stu2=[[Person alloc]initClasses:@"IOS8"
                                        andName:@"ASD"
                                         andAge:24];
        Person *stu3=[[Person alloc]initClasses:@"IOS7"
                                        andName:@"JYC"
                                         andAge:21];
        Person *stu4=[[Person alloc]initClasses:@"IOS7"
                                        andName:@"GFD"
                                         andAge:23];
        NSArray *arr=[NSArray arrayWithObjects:stu1,stu2,stu3,stu4,nil];

        NSArray *sortArr=[arr sortedArrayUsingSelector:@selector(compareWithClassAndName:)];
        for(Person *person in sortArr){
            NSLog(@"班级%@ 姓名%@ 年龄%d",person.classes,person.name,person.age);
        }
       NSLog(@"%@",sortArr);
       
    }
    return 0;
}

person.h

#import <Foundation/Foundation.h>

@interface Person : NSObject
@property NSString *classes;
@property NSString *name;
@property int age;
-(instancetype)initClasses:(NSString *)classes andName:(NSString *)name andAge:(int)age;
//instancetype  返回输入的对象  instancetype 可以反回和方法所在类相同类型的对象
-(NSComparisonResult)compareWithClassAndName:(Person *)person;
-(NSComparisonResult)compareWithAge:(Person *)person;

@end

person.m

#import "Person.h"

@implementation Person
-(instancetype)initClasses:(NSString *)classes andName:(NSString *)name andAge:(int)age{
    Person *person=[[Person alloc]init];
    person.classes=classes;
    person.name=name;
    person.age=age;
    return person;
}
-(NSComparisonResult)compareWithClassAndName:(Person *)person{
    NSComparisonResult result=[self.classes compare:person.classes];
    if(result==NSOrderedSame){ 
        return [self.name compare:person.name];//如果班级相同，则返回姓名排序的结果
    }else{
        return result;                          //如果班级不同，则返回班级排序结果
    }
}
-(NSComparisonResult)compareWithAge:(Person *)person{
    if(self.age==person.age){
        return NSOrderedSame;
    }else if(self.age>person.age){
        return NSOrderedDescending;
    }else{
        return NSOrderedAscending;
    }

}
-(NSString *)description{
    return [NSString stringWithFormat:@"class:%@ name:%@ age:%d",self.classes,self.name,self.age];
}

@end