.NET DateTime, different resolution when converting to and from OADate?
问题 I'm converting a DateTime to OADate. I was expecting to get the exact same DateTime when converting the OADate back, but now it has only millisecond resolution, and is therefore different. var a = DateTime.UtcNow; double oadate = a.ToOADate(); var b = DateTime.FromOADate(oadate); int compare = DateTime.Compare(a, b); //Compare is not 0; the date times are not the same Ticks from a: 634202170964319073 Ticks from b: 634202170964310000 The OADate double: 40437.290467951389 What is the reason for