Question

TimeOfDay文档没有比较运算符，并且原始比较不起作用。我现在唯一能想到的解决方案是将TimeOfDay转换为DateTime并使用DateTime的差分方法。

有人有更好的解决方案吗？

Answer 1

我通过将两个值都转换为分钟数，然后比较它们来计算差异：）

TimeOfDay now = TimeOfDay.now();
int nowInMinutes = now.hour * 60 + now.minute;

TimeOfDay testDate = TimeOfDay(hour: 2, minute: 20);
int testDateInMinutes = testDate.hour * 60 + testDate.minute;

Answer 2

我认为这不可能。您也可以在DateTime中使用.subtract

Answer 3

将其转换为双精度然后进行比较。

double toDouble(TimeOfDay myTime) => myTime.hour + myTime.minute/60.0

Answer 4

由于@Lucas的想法，您可以通过

计算小时和分钟

TimeOfDay yourTime ; 
TimOfDay nowTime = TimeOfDay.now()

double _doubleyourTime = yourTime.hour.toDouble() +
            (yourTime.minute.toDouble() / 60);
double _doubleNowTime = nowTime.hour.toDouble() +
            (nowTime.minute.toDouble() / 60);

double _timeDiff = _doubleOpenTime - _doubleNowTime;

double _hr = _timeDiff.truncate();
double _minute = (_timeDiff - _timeDiff.truncate()) * 60;

print('Here your Happy $_hr Hour and _minute min');

Answer 5

您无法真正比较2个TimeOfDay变量，因为您没有足够的信息。 Dart不知道您要比较哪个日期，月份和年份。如您所述，唯一的方法是将TimeOfDay转换为DateTime。

否则，您始终可以按照其他答案中的建议将TimeOfDay转换为double并计算差值。

Answer 6

Card(
    child: ListTile(
      onTap: () {
        showTimePicker(
          context: context,
          initialTime: TimeOfDay.now(),
        ).then((TimeOfDay time) {
          double _doubleyourTime =
              time.hour.toDouble() + (time.minute.toDouble() /60);
          double _doubleNowTime = TimeOfDay.now().hour.toDouble() +
              (TimeOfDay.now().minute.toDouble() / 60);`enter code here`
          if (_doubleyourTime > _doubleNowTime) {
           print('correct format')
            });
          } else {
           print('Sorry You can not set the time')
         
          }
        });
      },
      //dense: true,
      leading: Icon(Icons.timer),
      title: Text(
        'Today On Time',`enter code here`
      ),
    ),
  ),

Answer 7

extension TimeOfDayExtension on TimeOfDay {
  int compareTo(TimeOfDay other) {
    if (this.hour < other.hour) return -1;
    if (this.hour > other.hour) return 1;
    if (this.minute < other.minute) return -1;
    if (this.minute > other.minute) return 1;
    return 0;
  }
}

Answer 8

TimeOfDay n = TimeOfDay.now();
int nowSec = (n.hour * 60 + n.minute) * 60;
int veiSec = (t.hour * 60 + t.minute) * 60;
int dif = veiSec - nowSec;

Answer 9

我计算了两次之间的当前时间：

DateTime before;
DateTime later;
before = DateTime.now();
later = DateTime.now();
print(before.difference(later));

您可以计算到毫秒：

print(before.difference(Later).inMilliseconds);

Dart / Flutter如何比较两个TimeOfDay时间？

9 个答案: