这里有一个可以在本地使用的通用方法。

    // Takes a list and returns all records that have overlapping time ranges.
    public static IEnumerable<T> GetOverlappedTimes<T>(IEnumerable<T> list, Func<T, bool> filter, Func<T,DateTime> start, Func<T, DateTime> end)
    {
        // Selects all records that match filter() on left side and returns all records on right side that overlap.
        var overlap = from t1 in list
                      where filter(t1)
                      from t2 in list
                      where !object.Equals(t1, t2) // Don't match the same record on right side.
                      let in1 = start(t1)
                      let out1 = end(t1)
                      let in2 = start(t2)
                      let out2 = end(t2)
                      where in1 <= out2 && out1 >= in2
                      let totover = GetMins(in1, out1, in2, out2)
                      select t2;

        return overlap;
    }

    public static void TestOverlap()
    {
        var tl1 = new TempTimeEntry() { ID = 1, Name = "Bill", In = "1/1/08 1:00pm".ToDate(), Out = "1/1/08 4:00pm".ToDate() };
        var tl2 = new TempTimeEntry() { ID = 2, Name = "John", In = "1/1/08 5:00pm".ToDate(), Out = "1/1/08 6:00pm".ToDate() };
        var tl3 = new TempTimeEntry() { ID = 3, Name = "Lisa", In = "1/1/08 7:00pm".ToDate(), Out = "1/1/08 9:00pm".ToDate() };
        var tl4 = new TempTimeEntry() { ID = 4, Name = "Joe", In = "1/1/08 3:00pm".ToDate(), Out = "1/1/08 8:00pm".ToDate() };
        var tl5 = new TempTimeEntry() { ID = 1, Name = "Bill", In = "1/1/08 8:01pm".ToDate(), Out = "1/1/08 8:00pm".ToDate() };
        var list = new List<TempTimeEntry>() { tl1, tl2, tl3, tl4, tl5 };
        var overlap = GetOverlappedTimes(list, (TempTimeEntry t1)=>t1.ID==1, (TempTimeEntry tIn) => tIn.In, (TempTimeEntry tOut) => tOut.Out);

        Console.WriteLine("\nRecords overlap:");
        foreach (var tl in overlap)
            Console.WriteLine("Name:{0} T1In:{1} T1Out:{2}", tl.Name, tl.In, tl.Out);
        Console.WriteLine("Done");

        /*  Output:
            Records overlap:
            Name:Joe T1In:1/1/2008 3:00:00 PM T1Out:1/1/2008 8:00:00 PM
            Name:Lisa T1In:1/1/2008 7:00:00 PM T1Out:1/1/2008 9:00:00 PM
            Done
         */
    }

如果您提供一个日期范围作为输入，并希望找出它是否与数据库中的现有日期范围重叠，则以下条件可以成功满足您的需求

假设您从表单输入中提供了@StartDate和@EndDate。

条件是：

如果@StartDate在existingStartDate之前，而在existing EndDate之后，那么我们可以说@StartDate's在现有日期范围的中间，因此我们可以断定它将重叠

@StartDate >=existing.StartDate And @StartDate <= existing.EndDate) 

如果@StartDate在现有StartDate之后，而@EndDate在现有的StartDate之前，我们可以说它将重叠

 (@StartDate <= existing.StartDate And @EndDate >= existing.StartDate)

如果@StartDate晚于现有的StartDate，而@EndDate先于现有的EndDate，我们可以得出结论，所提供的日期范围吞噬了现有的日期范围，因此重叠

 (@StartDate <= existing.StartDate And @EndDate >= existing.EndDate))

如果任何条件成立，则提供的日期范围与数据库中的现有日期范围重叠。

使用Java util.Date，这里是我所做的。

    public static boolean checkTimeOverlaps(Date startDate1, Date endDate1, Date startDate2, Date endDate2)
    {
        if (startDate1 == null || endDate1 == null || startDate2 == null || endDate2 == null)
           return false;

        if ((startDate1.getTime() <= endDate2.getTime()) && (startDate2.getTime() <= endDate1.getTime()))
           return true;

        return false;
    }

我认为，在以下情况下，两个范围重叠就足够了：

(StartDate1 <= EndDate2) and (StartDate2 <= EndDate1)

这是我的Java解决方案，它也适用于无限区间

private Boolean overlap (Timestamp startA, Timestamp endA,
                         Timestamp startB, Timestamp endB)
{
    return (endB == null || startA == null || !startA.after(endB))
        && (endA == null || startB == null || !endA.before(startB));
}

记住解决方案的一个简单方法是最小（结束）>最大（开始）