iOS 数组和字典排序
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 =@{@"price":@"30",@"name":@"liu"}; 3 NSDictionary *dic2 =@{@"price":@"150",@"name":@"huang"}; 4 NSDictionary *dic3 =@{@"price":@"37",@"name":@"yoyu"}; 5 NSDictionary *dic4 =@{@"price":@"25",@"name":@"yofu"}; 6 NSDictionary *dic5 =@{@"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 }
