Cleanest way to check if a date is in a range (Nullable Date)

Question

What is the cleanest way to check if a supplied date is in a given date range? For example:

DateTime? maxDate
DateTime? minDate
DateTime? userDate

I want to check if the userDate is in the range. Where min or max can be null.

So for example:

minDate = new DateTime(2017, 1, 1);
maxDate = null;
userDate = new DateTime(2017, 5, 3);

In this scenario userDate would be in the range since it's greater then the minDate and no maxDate was specified.

I thought about using DateTime.Compare but it seems that I would create a mess of if/then statements to check userDate to the minDate and maxDate variables since the DateTime.Compare will only compare 2 dates at a time.

score 2 · Accepted Answer · answered Jun 05 '17 at 23:52

2

Assuming null min/max would mean 'unbounded' in that direction, you could take advantage of the fact that DateTime itself has bounds.

For example:

public bool IsDateInRange(DateTime value, DateTime? min, DateTime? max)
{
    //Use provided min/max times if they were not null. Fallback to Min/Max supported values from DateTime
    min = min ?? DateTime.MinValue;
    max = max ?? DateTime.MaxValue;

    return value >= min && value <= max;
}

I'm not really sure how you would want to handle the case where userDate = null. Is that ever in range? So my example function doesn't allow it. For that case, you could handle it explicitly if you want to define that behavior.

answered Jun 05 '17 at 23:52

Khalos

2,335
1
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1

Good answer. On a side note, you should [convert to UTC when comparing dates](https://stackoverflow.com/questions/6930489/safely-comparing-local-and-universal-datetimes) or else you may end up with an incorrect comparison, especially if you are comparing times that fall within the extra hour added or removed for DST, – John Wu Jun 05 '17 at 23:58
To add to this, you could use minDate.GetValueOrDefault(DateTime.MinValue) – Tony Basallo Jun 06 '17 at 03:26

score 1 · Answer 2 · answered Nov 05 '19 at 11:42

You can do like this:

  public static bool IsInRange(this DateTime dateToCheck, DateTime? startDate, DateTime? endDate)
    {
        return (startDate.HasValue && dateToCheck.Date >= startDate.Value.Date) &&
               (endDate.HasValue && dateToCheck.Date <= endDate.Value.Date);
    }

score 0 · Answer 3 · answered Jun 05 '17 at 23:52

0

if((minDate == null || minDate < userDate) && (maxDate == null || maxDate > userDate)) {
    // Do something
}

answered Jun 05 '17 at 23:52

Frederik Hansen

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Cleanest way to check if a date is in a range (Nullable Date)

3 Answers3