一、数组排序
数组排序方式1：
1 //初始化可变数组
2 NSMutableArray *arr1=[NSMutableArray arrayWithObjects:@"giu",@"min",@"Deng",@"liumin", nil];
3 //字符串排序
4 //创建排序描述符对象NSSortDescriptor，key为空，ascending：升序
5 NSSortDescriptor *decri =[NSSortDescriptor sortDescriptorWithKey:nil ascending:YES];
6 //定义一个数组，用来盛放排序条件
7 NSArray *des =[NSArray arrayWithObject:decri];
8 //开始排序
9 [arr1 sortUsingDescriptors:des];
10 //打印排序内容
11 for (int i=0; i<arr1.count; i++)
12 {
13 NSLog(@"arr=%@",[arr1 objectAtIndex:i]);
14 }
数组排序方式2：
1 NSMutableArray *arr2=[NSMutableArray arrayWithObjects:@"c", @"A",@"z",@"D",nil];
2
3 //区分大小写排序 自带compar方法 选择排序
4 [arr2 sortUsingSelector:@selector(compare:)];
5 for (int i=0; i<arr2.count; i++)
6 {
7 NSLog(@"arr2=%@",[arr2 objectAtIndex:i]);
8 }
二、字典的排序
1 //创建5个排序对象
2 NSDictionary *dic1 [email protected]{@"price":@"30",@"name":@"liu"};
3 NSDictionary *dic2 [email protected]{@"price":@"150",@"name":@"huang"};
4 NSDictionary *dic3 [email protected]{@"price":@"37",@"name":@"yoyu"};
5 NSDictionary *dic4 [email protected]{@"price":@"25",@"name":@"yofu"};
6 NSDictionary *dic5 [email protected]{@"price":@"172",@"name":@"yosu"};
7 //将这些对象放进数组
8 NSArray *arr =[NSArray arrayWithObjects:dic1,dic2,dic3,dic4, dic5,nil];
9 //调用数组排序方法
10 NSArray *arr2 = [arr sortedArrayUsingComparator:^NSComparisonResult(id obj1, id obj2)
11 {
12 //取出对象里的一个值作比较，根据大小返回结果
13 NSString *c = [obj1 valueForKey:@"price"];
14 NSString *d = [obj2 valueForKey:@"price"];
15 int a =[c intValue]; //转成整形int比较
16 int b =[d intValue];
17 //按照降序排列，如果升序就返回结果对换
18 if (a > b)
19 {
20 return NSOrderedAscending;
21 }else
22 {
23 return NSOrderedDescending;
24 }
25
26 }];
27 //循环遍历排序后的字典数组
28 for (NSDictionary *dic in arr2)
29 {
30 NSLog(@"%@",dic);
31 }
时间： 2024-11-07 19:32:26