您可以传递位置的 DateTime 和 TimeZone 并将提供的 DateTime 转换为 UTC
在此处检查此示例
       string DisplayName = "custom standard name here";//custom Standard Name to display eg: Kathmandu
       string StandardName = "custom standard name here"; // custom Standard Name eg: Asia/Kathamandu, Nepal
       string YourDate="27-03-2019 20:24:56"; // this DateTime doesn't contain any timeZone
       TimeSpan Offset = new TimeSpan(+5, 30, 00);// your TimeZone offset eg: timeZone of Nepal is +5:45
       TimeZoneInfo TimeZone = TimeZoneInfo.CreateCustomTimeZone(StandardName, Offset, DisplayName, StandardName);
       var RawDateTime = DateTime.SpecifyKind(DateTime.Parse(YourDate), DateTimeKind.Unspecified);// I all it RawDateTime Since it doesn't contain any TimeSpan
       DateTime UTCDateTime = TimeZoneInfo.ConvertTimeToUtc(RawDateTime, TimeZone);
       Console.WriteLine(UTCDateTime);