如何创建NSDate日期对象？

// 导入Foundation框架
#import <Foundation/Foundation.h>

int main(int argc, const char * argv[]) {
    @autoreleasepool {
        // 创建一个NSDate对象，表示当前日期和时间
        NSDate *currentDate = [NSDate date];
        NSLog(@"当前日期和时间：%@", currentDate);
        
        // 创建一个NSDate对象，表示指定的日期和时间
        NSDateComponents *components = [[NSDateComponents alloc] init];
        [components setYear:2022];
        [components setMonth:12];
        [components setDay:31];
        [components setHour:23];
        [components setMinute:59];
        [components setSecond:59];
        
        NSCalendar *calendar = [NSCalendar currentCalendar];
        NSDate *customDate = [calendar dateFromComponents:components];
        NSLog(@"指定日期和时间：%@", customDate);
    }
    return 0;
}