using System;

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const long timestamp = 1480024800000;

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var dateTime = new DateTime(1970, 1, 1, 0, 0, 0, 0, DateTimeKind.Utc);

dateTime = dateTime.AddMilliseconds(timestamp);

Console.WriteLine(dateTime);

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DateTime dateTime2 = dateTime.ToLocalTime();

Console.WriteLine(dateTime2);

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