排序(I)

NSSortDescriptor 排序

Person类

 #import <Foundation/Foundation.h>

 @interface Person : NSObject

 @property (nonatomic, copy) NSString *name;
 @property (nonatomic, assign) BOOL sex;
 @property (nonatomic, assign) double height;
 @property (nonatomic, assign) int age;

 @end

排序调用方法

 - (void) test {

     NSArray *names = @[@"夏侯惇", @"貂蝉", @"诸葛亮", @"张三", @"李四", @"流火绯瞳", @"流火", @"李白", @"张飞", @"韩信", @"范冰冰", @"赵丽颖"];
     NSArray *ages = @[@, @, @, @, @, @, @, @, @, @, @, @];
     NSArray *heights = @[@, @, @, @, @, @, @, @, @, @, @, @];

     NSMutableArray *peoples = [NSMutableArray arrayWithCapacity:names.count];
     for (int i = ; i<names.count; i++) {

         Person *pe = [[Person alloc]init];
         pe.name = names[i];
         pe.age = [ages[i] intValue];
         pe.height = [heights[i] doubleValue];
         [peoples addObject:pe];
     }

     NSSortDescriptor *sort = [NSSortDescriptor sortDescriptorWithKey:@"age" ascending:YES];

     [peoples sortUsingDescriptors:@[sort]];

     // 输出排序结果
     for (Person *people in peoples) {
         NSLog(@"------------->age: %d,height: %f name: %@\n", people.age,people.height, people.name);
     }

 }

参数
key : 排序key, 某个对象的属性名称; 如果对字符串进行排序, 则传nil
ascending : 是否升序, YES-升序, NO-降序

打印结果：

2018-05-19 19:11:43.904288+0800 Test[7264:81290] ------------->age: 15,height: 174.000000 name: 流火

2018-05-19 19:11:43.904436+0800 Test[7264:81290] ------------->age: 27,height: 176.000000 name: 流火绯瞳

2018-05-19 19:11:43.904527+0800 Test[7264:81290] ------------->age: 30,height: 160.000000 name: 赵丽颖

2018-05-19 19:11:43.904632+0800 Test[7264:81290] ------------->age: 32,height: 170.000000 name: 夏侯惇

2018-05-19 19:11:43.904732+0800 Test[7264:81290] ------------->age: 32,height: 163.000000 name: 貂蝉

2018-05-19 19:11:43.904832+0800 Test[7264:81290] ------------->age: 32,height: 165.000000 name: 张三

2018-05-19 19:11:43.904924+0800 Test[7264:81290] ------------->age: 32,height: 163.000000 name: 李四

2018-05-19 19:11:43.905017+0800 Test[7264:81290] ------------->age: 34,height: 178.000000 name: 韩信

2018-05-19 19:11:43.905098+0800 Test[7264:81290] ------------->age: 44,height: 167.000000 name: 范冰冰

2018-05-19 19:11:43.905186+0800 Test[7264:81290] ------------->age: 45,height: 180.000000 name: 诸葛亮

2018-05-19 19:11:43.905271+0800 Test[7264:81290] ------------->age: 55,height: 186.000000 name: 张飞

2018-05-19 19:11:43.905359+0800 Test[7264:81290] ------------->age: 67,height: 183.000000 name: 李白