我有以下格式的字典数组。
myarary = {day = 0; 小时 = 1; 值 = 0;},{天 = 0; 小时 = 2; 值 = 0;}.... {第 6 天 =1; 小时=23；值 =1;}
所以基本上是 7 天，每天 24 小时，每小时值为 1 或 0。因此我的数组中共有 168 个字典。
现在我的任务是提取给定日期的几个小时范围内的值。例如，对于第 6 天，我必须提取 2、9 和 15 到 18 之间的另一个时间段，依此类推。
我设法解决了这个问题，使用以下格式的嵌套 for 循环
for (i =< start_of_hour_slot;i=<last_hour_of_slot); i++)
for(j = 0; j<=6; j++)
现在这可行，但是它太长了，而且我的代码充满了循环，必须有更简单的快速枚举方法吗？
其次，我的 for 循环没有给我灵活性。
我喜欢在一个位置，我可以简单地提取让我们说第 7 天，三个不同的时间段，以及值。
或者可能持续多天，例如第 3、4、5 天、第 2-9、11、15 天...
正如@vadian 建议的那样， NSCompoundPredicate 应该适用于您要完成的工作。看起来您在评论中发布的 NSPredicate 中可能有一些拼写错误，这就是它无法解析的原因。
#import "ViewController.h"
@interface ViewController ()
@property (strong, nullable) NSArray <NSDictionary *> *generatedArray;
- (NSArray <NSDictionary *> *)_generateFakeDictionaryArray;
- (NSPredicate *)_predicateForDays:(NSArray <NSNumber *> *)days andHours:(NSArray <NSNumber *> *)hours;
- (NSPredicate *)_predicateForDays:(NSArray <NSNumber *> *)days andHoursBetween:(NSArray <NSNumber *> *)hoursBetween;
- (NSPredicate *)_predicateForDaysBetween:(NSArray <NSNumber *> *)daysBetween andHours:(NSArray <NSNumber *> *)hours;
- (NSPredicate *)_predicateForDaysBetween:(NSArray <NSNumber *> *)daysBetween andHoursBetween:(NSArray <NSNumber *> *)hoursBetween;
@end
@implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
self.generatedArray = [self _generateFakeDictionaryArray];
}
- (void)viewDidAppear:(BOOL)animated {
// one day multiple hour slots
NSPredicate *specificDaysSpecificHours = [self _predicateForDays:@[@(6)] andHours:@[@(7), @(8), @(22)]];
// multiple days hoursBetween
NSPredicate *daysBetweenHoursBetween = [self _predicateForDaysBetween:@[@(3), @(5)] andHoursBetween:@[@(2), @(9)]];
// days between, specific hours
NSPredicate *daysBetweenSpecificHours = [self _predicateForDaysBetween:@[@(3), @(5)] andHours:@[@(11), @(15)]];
NSCompoundPredicate *compPred = [NSCompoundPredicate orPredicateWithSubpredicates:@[specificDaysSpecificHours, daysBetweenHoursBetween, daysBetweenSpecificHours]];
NSArray <NSDictionary *> *filteredArray = [self.generatedArray filteredArrayUsingPredicate:compPred];
NSLog(@"Filtered array = %@", filteredArray);
}
- (NSArray <NSDictionary *> *)_generateFakeDictionaryArray {
NSInteger daysInWeek = 7;
NSInteger hoursInDay = 24;
NSMutableArray *dictArray = [NSMutableArray arrayWithCapacity:hoursInDay * daysInWeek];
for (NSInteger day = 0; day < daysInWeek; day++) {
for (NSInteger hour = 0; hour < hoursInDay; hour++) {
NSDictionary *dayHourDict = @{@"day" : @(day), @"hour" : @(hour), @"value" : @(arc4random() % 2)};
[dictArray addObject:dayHourDict];
}
}
return [NSArray arrayWithArray:dictArray];
}
- (NSPredicate *)_predicateForDays:(NSArray <NSNumber *> *)days andHours:(NSArray <NSNumber *> *)hours {
return [NSPredicate predicateWithFormat:@"day IN %@ AND hour IN %@", days, hours];
}
- (NSPredicate *)_predicateForDays:(NSArray <NSNumber *> *)days andHoursBetween:(NSArray <NSNumber *> *)hoursBetween {
return [NSPredicate predicateWithFormat:@"day IN %@ AND hour BETWEEN %@", days, hoursBetween];
}
- (NSPredicate *)_predicateForDaysBetween:(NSArray <NSNumber *> *)daysBetween andHours:(NSArray <NSNumber *> *)hours {
return [NSPredicate predicateWithFormat:@"day BETWEEN %@ AND hour IN %@", daysBetween, hours];
}
- (NSPredicate *)_predicateForDaysBetween:(NSArray <NSNumber *> *)daysBetween andHoursBetween:(NSArray <NSNumber *> *)hoursBetween {
return [NSPredicate predicateWithFormat:@"day BETWEEN %@ AND hour BETWEEN %@", daysBetween, hoursBetween];
}
@end
生成此作为输出：
Filtered array = (
{
day = 3;
hour = 2;
value = 1;
},
{
day = 3;
hour = 3;
value = 0;
},
{
day = 3;
hour = 4;
value = 0;
},
{
day = 3;
hour = 5;
value = 1;
},
{
day = 3;
hour = 6;
value = 0;
},
{
day = 3;
hour = 7;
value = 0;
},
{
day = 3;
hour = 8;
value = 0;
},
{
day = 3;
hour = 9;
value = 1;
},
{
day = 3;
hour = 11;
value = 0;
},
{
day = 3;
hour = 15;
value = 1;
},
{
day = 4;
hour = 2;
value = 1;
},
{
day = 4;
hour = 3;
value = 1;
},
{
day = 4;
hour = 4;
value = 1;
},
{
day = 4;
hour = 5;
value = 1;
},
{
day = 4;
hour = 6;
value = 1;
},
{
day = 4;
hour = 7;
value = 1;
},
{
day = 4;
hour = 8;
value = 0;
},
{
day = 4;
hour = 9;
value = 1;
},
{
day = 4;
hour = 11;
value = 1;
},
{
day = 4;
hour = 15;
value = 1;
},
{
day = 5;
hour = 2;
value = 1;
},
{
day = 5;
hour = 3;
value = 0;
},
{
day = 5;
hour = 4;
value = 1;
},
{
day = 5;
hour = 5;
value = 0;
},
{
day = 5;
hour = 6;
value = 0;
},
{
day = 5;
hour = 7;
value = 1;
},
{
day = 5;
hour = 8;
value = 1;
},
{
day = 5;
hour = 9;
value = 0;
},
{
day = 5;
hour = 11;
value = 0;
},
{
day = 5;
hour = 15;
value = 1;
},
{
day = 6;
hour = 7;
value = 1;
},
{
day = 6;
hour = 8;
value = 1;
},
{
day = 6;
hour = 22;
value = 1;
}
)
https://developer.apple.com/documentation/foundation/nspredicate?language=objc
https://developer.apple.com/documentation/foundation/nscompoundpredicate?language=objc
你可以改变你的数组大小和格式，既然你的数据是清楚的，只需要将数组大小设置为168，并将值0或1直接放入数组中。前 24 个元素将数组放入 day0 值，接下来的 24 个元素放入 day1 值，...，最后 24 个元素放入 day6 值。如果要提取第 3,4,5 天 2-9, 11,15 的值，只需获取 3*6+2 ~ 3*6+9, 4*6+11, 5*6 的元素索引+15 在数组中。