public void Between()
{
var date = new DateTimeOffset(2015, 8, 7, 13, 26, 30, TimeSpan.Zero);
Assert.IsTrue(date.Between(date.AddMonths(-3), date.AddMonths(3)));
Assert.IsTrue(date.AddHours(36).Between(date.AddMonths(-3), date.AddMonths(3)));
Assert.IsFalse(date.AddMonths(6).Between(date.AddMonths(-3), date.AddMonths(3)));
Assert.IsFalse(date.AddHours(-2).Between(date, date.AddMonths(3)));
Assert.IsTrue(date.Between(date.AddMonths(-3), date.AddMonths(3), false));
Assert.IsTrue(date.AddHours(36).Between(date.AddMonths(-3), date.AddMonths(3), false));
Assert.IsFalse(date.AddMonths(6).Between(date.AddMonths(-3), date.AddMonths(3), false));
Assert.IsTrue(date.AddHours(-2).Between(date, date.AddMonths(3), false));
Assert.IsFalse(date.AddHours(-24).Between(date, date.AddMonths(3), false));
}
void CheckValidityAt(DateTimeOffset usedOn)
{
if (!usedOn.Between(IssuedOn, ExpiresOn))
throw new Exception("Invalid credit card.");
}
