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//创建一个数组 NSArray *array = @[@"one", @"two", @"three", @"four", @"six"]; //创建一个排序条件,也就是一个NSSortDescriptor对象 //其中第一个参数为数组中对象要按照什么属性来排序(比如自身、姓名,年龄等) //第二个参数为指定排序方式是升序还是降序 //ascending 排序的意思,默认为YES 升序 NSSortDescriptor *des = [[NSSortDescriptor alloc] initWithKey:@"self" ascending:YES]; NSArray *newArray = [array sortedArrayUsingDescriptors:@[des]]; NSLog(@"%@",newArray);
可以用sortedArrayUsingDescriptors:方法实现把多个排序条件放到数组中,实现多条件排序,按数组先后顺序,先加入的优先级高
//创建一个Person类 Person *p1 = [[Person alloc] initWithName:@"zhonger" age:@"19"]; Person *p2 = [[Person alloc] initWithName:@"zhubada" age:@"11"]; Person *p3 = [[Person alloc] initWithName:@"zhubada" age:@"1"]; Person *p4 = [[Person alloc] initWithName:@"zhubada" age:@"33"]; Person *p5 = [[Person alloc] initWithName:@"hehehe" age:@"38"]; NSArray *person = @[p1, p2, p3, p4, p5]; NSSortDescriptor *des1 = [[NSSortDescriptor alloc]initWithKey:@"name" ascending:YES]; NSSortDescriptor *des2 = [[NSSortDescriptor alloc] initWithKey:@"age" ascending:NO]; NSArray *newArray1 = [person sortedArrayUsingDescriptors:@[des1,des2]]; NSLog(@"%@",newArray1);
使用NSSortDesriptor进行数组排序有三步
1.创建一个用来排序的数组
2.创建一个排序条件,初始化中需要指定按照数组中对象的什么属性进行排序,升序或者降序
3.数组根据排序条件进行排序,得到一个排序之后的数组(如果是可变数组,不会生成新数组,还是本身)
使用的sortedArrayUsingSelecor:的方法,就不需要创建NSSortDescriptor
NSArray *strArray = @[@"zhonger", @"zhubada", @"qiuxiang", @"tangbohu", @"honghuang"]; NSArray *nesStr = [strArray sortedArrayUsingSelector:@selector(compare:)]; //SEL 只能用@selector(方法名)给定,并且,如果数组使用这个数组进行排序,此方法必须是返回值为NSComparisionResult NSLog(@"newStr is %@",nesStr); NSArray *personNewArray = [person sortedArrayUsingSelector:@selector(compareByName:)]; NSLog(@"--%@",personNewArray);
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原文地址:http://www.cnblogs.com/Walking-Jin/p/5468371.html