Iphone 从xcode 4中的电话获取时间时出错？

我试图从手机时钟中提取时间，但无法使用此代码提取时间

NSDate *today = [NSDate date];
    NSCalendar *gregorian = [[NSCalendar alloc]
                             initWithCalendarIdentifier:NSGregorianCalendar];

NSInteger hour = [components hour];
    NSInteger minute = [components minute];
    NSInteger second = [components second];

用这个

NSDate *today = [NSDate date];
    NSCalendar *gregorian = [[NSCalendar alloc]
                             initWithCalendarIdentifier:NSGregorianCalendar];
    NSDateComponents *components =
    [gregorian components:(NSHourCalendarUnit | NSMinuteCalendarUnit | NSSecondCalendarUnit) fromDate:today];

    NSInteger hour = [components hour];
    NSInteger minute = [components minute];
    NSInteger second = [components second];

您在代码中遗漏了一行。

请使用此选项

NSDate *today = [NSDate date];
    NSCalendar *gregorian = [[NSCalendar alloc]
                             initWithCalendarIdentifier:NSGregorianCalendar];
    NSDateComponents *components =
    [gregorian components:(NSHourCalendarUnit | NSMinuteCalendarUnit | NSSecondCalendarUnit) fromDate:today];

    NSInteger hour = [components hour];
    NSInteger minute = [components minute];
    NSInteger second = [components second];

你漏了一行代码