iOS 获取时间戳
NSTimeInterval interval = [[NSDate date] timeIntervalSince1970] * 1000;
iOS 时间戳转换为时间
NSString *str=@"1368082020";//时间戳
NSTimeInterval time=[str doubleValue]+28800;//因为时差问题要加8小时 == 28800 sec
NSDate *detaildate=[NSDate dateWithTimeIntervalSince1970:time];
NSLog(@"date:%@",[detaildate description]);