Windows Runtime DateTime and TimeSpan Representations

The JavaScript representation of dates and times is different from the Windows Runtime version. The Windows Runtime DateTime structure is represented in JavaScript as a Date that has a backing store that matches the DateTime data (and has a different range and precision from the JavaScript Date). If you modify this custom Date object, it becomes a standard JavaScript Date and loses precision. JavaScript Date values can be passed to a Windows Runtime DateTime and will be range-checked, which might result in marshaling exceptions.

The Windows Runtime TimeSpan structure is converted to milliseconds and returned as a JavaScript number.

See Also

Using the Windows Runtime in JavaScript