The AJAX JSON serializer in ASP.NET encodes a DateTime instance as a JSON string. During its pre-release cycles, ASP.NET AJAX used the format "@ticks@", where ticks represents the number of milliseconds since January 1, 1970 in Universal Coordinated Time (UTC). A date and time in UTC like November 29, 1989, 4:55:30 AM would be written out as "@62831853071@." Although simple and straightforward, this format cannot differentiate between a serialized date and time value and a string that looks like a serialized date but is not meant to be deserialized as one. Consequently, the ASP.NET AJAX team made a change for the final release to address this problem by adopting the "\/Date(ticks)\/" format.
The new format relies on a small trick to reduce the chance for misinterpretation. In JSON, a forward-slash (/) character in a string can be escaped with a backslash (\) even though it is not strictly required. Taking advantage of this, the ASP.NET AJAX team mod