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How to get a date in a link? MVC 5

I'm implementing a web page, doing the homepage, I have a button that the user uses in order to recover his password (due to forgetting it). Then my program sends him a link to his e-mail after verifying it in the database. This link let's the user reset his password.
I want to add a date to the link, so that if when the user gets redirected to the reset pass page, it's date is verified and if it is higher than 1 hour it tells the user he needs to re-do the process.
Do I use,
DateTime saveNow = DateTime.Now;?
Sorry for the bad English, thank you

You can use DateTime.Now.Ticks. This gives you an integer that can easily be posted in an url and then be converted to a DateTime again.

Ok, this doesn't quite answer your question, however there is a better way of handling password reset timeouts. If you are using the following code in your action:
WebSecurity.GeneratePasswordResetToken(emailAddress);
You can also pass in a second parameter which specifies how long the password token is valid for in minutes otherwise the default time out is 24 hours.
From there you can validate the token is valid in a bool type action by using something similar to the below:
var repository = repository.GetByPasswordResetToken(resetToken);
isValid = membership != null && repository.PasswordVerificationTokenExpirationDate > DateTime.Now;
This is based on the assumption you are utilising WebMatrix within your server side logic.

How do you specify an exception in an iCal feed?

I am working on creating an iCal feed for our application. Things are going well. I have everything working except exceptions. For example when you schedule a recurring event and need to cancel a day, I am using the EXDATE tag in the feed and that is working fine for removing a scheduled occurrence.
The issues is if you have a recurring event that starts today # 2pm and recurrs 5 times. In our application the user can change any one of those weeks to start # 3pm if needed. How to I specify that in the iCal feed?
I have been looking at the documentation, but must be missing something...
Thanks a bunch!!

Drowsy is on the right track.
The UID's MUST match so that the adjusment is recognised as
belonging to the original event.
The Recurrence Id matches it to the instance of the recurring sequence that is being modified.
This is because of course one might be changing the date and time
as well as other changes and one doesn't want the original
instance there generated by the recurring spec, as well as the
modification.
And yes finally the sequence id must be there so
that one knows the sequence or layer of modifications in case
there are several.
For example - here's a dump of what google calendar generates if you modify a recurring event.
BEGIN:VEVENT
DTSTART;TZID=Australia/Sydney:20140325T084000
DTEND;TZID=Australia/Sydney:20140325T101000
DTSTAMP:20140327T060506Z
UID:vu2d4gjdj4mpfuvas53qi32s7k#google.com
RECURRENCE-ID;TZID=Australia/Sydney:20140325T083000
CREATED:20131216T033331Z
DESCRIPTION:
LAST-MODIFIED:20140327T060215Z
LOCATION:
SEQUENCE:1
STATUS:CONFIRMED
SUMMARY:test Event
TRANSP:OPAQUE
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Australia/Sydney:20140128T083000
DTEND;TZID=Australia/Sydney:20140128T100000
RRULE:FREQ=WEEKLY;UNTIL=20141208T213000Z;BYDAY=TU
DTSTAMP:20140327T060506Z
UID:vu2d4gjdj4mpfuvas53qi32s7k#google.com
CREATED:20131216T033331Z
DESCRIPTION:
LAST-MODIFIED:20140222T101012Z
LOCATION:
SEQUENCE:0
STATUS:CONFIRMED
SUMMARY:Test event
TRANSP:OPAQUE
END:VEVENT

I believe as long as you generate a record with a RECURRENCE-ID based on the original time, and using the original UID you should be able to set the DTSTART and DTEND values for a single instance. You would need to increment the SEQUENCE too. That should trigger updates on client software.

What would be the best way to synchronize my application's time with outside server's time?

I was thinking of changing system's local time to server's time and then use it but I bet there are other ways to do this. I've been trying to find something like a clock in c#, but couldnt find anything. I'm receiving server's time in a DateTime format.
edit:
I need my application to use while working same time server does. I just want to get server's time once and after that, make my application work in a while loop using the time I've obtained from the server. There might be a difference between my system's time and server's time (even 5 seconds) and that's why I want to do this.

It's not entirely clear what you mean, but you could certainly create your own IClock interface which you'd use everywhere in code, and then write an implementation of that which is regularly synchronized with your server (or with NTP).
My Noda Time project already uses the idea of an injectable clock - not for synchronization purposes, but for testability. (A time service is basically a dependency.) Basically the idea is workable :) You may well not find anything which already does this, but it shouldn't be too hard to write. You'll want to think about how to adjust time though - for example, if the server time gets ahead of your "last server time + local time measurements" you may want to slew it gradually rather than having a discrete jump.
This is always assuming you do want it to be local to your application, of course. Another alternative (which may well not be appropriate, depending on your context) is to require that the host runs a time synchronization client (I believe Windows does by default these days) and simply start failing if the difference between your server and the client gets too large. (It's never going to be exactly in sync anyway, or at least not for long - you'll need to allow for some leeway.)

The answer #JonSkeet's provided to synch the times looks good, I just wanted to point out some things.
As #Alexei already said, users require admin privileges to be able to change their local time (in Windows as least), but there may also be other issues that can cause the time to be out of synch (bad internet connection, hacks etc.). This means there is no guarantee that the client time is indeed the same as the server time, so you will at least need to check the time the request was received serverside anyway. Plus there might also be a usability issue at hand here, would I want an application to be able change the time of my own local machine? Hell no.
To sum things up:
Check the time of the request serverside at least
Don't change the time of the client machine but show some kind of indicator in your application
How to handle the indicator in your application can be done in various ways.
Show a clock in your application (your initial idea) that is periodically synched with the server
Show some kind of countdown ("you can submit after x seconds.."), push a resetCountdown request to the clients when a request is received.
Enable a 'send button' or what ever you have, this would work kind of similar to the countdown.
Just remember, it's nearly impossible validate a request such as this clientside. So you have to build in some checks serverside!
I actually wanted to write a comment but it got kind of long.. :)

Okay a bit of necromancy as this is 6 years old, but had to deal with a similar problem for a network game.
Employed a technique I referred to as "marco-polo" for reasons that will be obvious soon. It requires the two clocks to be able to exchange messages, and its accuracy is dependent on how fast they can do that.
Disclaimer: I am fairly certain I am not the first to do this, and that this is the most rudimentary way to synchronize two clocks. Still I didn't find a documented way of doing so.
At Clock B (The clock we're trying to synchronize) we do the following ::
// Log the timestamp
localTime_Marco_Send = DateTime.UtcNow;
// Send that to clock A
SendSyncRequest();
// Wait for an answer
Sleep(..);
At Clock A (the reference clock) we have the following handler ::
// This is triggered by SendSyncRequest
OnReceiveSyncRequest()
{
// We received "Marco" - Send "Polo"
SendSyncReply(DateTime.UtcNow);
}
And back at Clock B ::
// This is triggered by SendSyncReply
OnReceiveSyncReply(DateTime remoteHalfTime)
{
// Log the time we received it
DateTime localTime_Polo_Receive = DateTime.UtcNow;
// The remote time is somewhere between the two local times
// On average, it will be in the middle of the two
DateTime localHalfTime = localTime_Marco_Send +
(localTime_Polo_Receive - localTime_Marco_Send) / 2;
// As a result, the estimated dT from A to B is
TimeSpan estimatedDT_A_B = localHalfTime - remoteHalfTime;
}
As a result we now have access to a nifty TimeSpan we can subtract from our current local time to estimate the remote time
DateTime estimatedRemoteTime = DateTime.UtcNow - estimatedDT_A_B;
The accuracy of this estimate is subject to the Round Trip Time of send-receive-send-receive, and you should also account for Clock drift (you should be doing this more than once):
Round-trip-time. If it were instant, you'd have the exact dT. If it takes 1 second to come and return, you don't know if the delay was on the sending or the receiving. As a result, your error is 0 < e < RTT, and on average will be RTT/2. If you know send (or receive) takes more than the other, use that to your advantage - the time you received is not the half-time, but is shifted relatively to how long each leg takes
Clock drift. CPU clocks drift, maybe 1s per day. So poll again once potential drift may play an important role.

Your server should always save the time in UTC mode.
You save time in UTC like this in the server:
DateTime utcTime = new DateTime(0, DateTimeKind.Utc);
or:
DateTime utcTimeNow = DateTime.UtcNow;
In the client, when you get the time which is stored in utc you can sonvert it to local time like this:
public DateTime ToLocalTime(DateTime utcTime)
{
//Assumes that even if utcTime kind is no properly deifned it is indeed UTC time
DateTime serverTime= new DateTime(utcTime.Ticks, DateTimeKind.Utc);
return TimeZoneInfo.ConvertTimeFromUtc(serverTime, m_localTimeZone);
}
If You want to change your local time zone , here is a code example on how to read time zone to use from config:
string localTimeZoneId = sysParamsHelper.ReadString(LOCAL_TIME_ZONE_ID_KEY, LOCAL_TIME_ZONE_DEFAULT_ID);
ReadOnlyCollection<TimeZoneInfo> timeZones = TimeZoneInfo.GetSystemTimeZones();
foreach (TimeZoneInfo timeZoneInfo in timeZones)
{
if(timeZoneInfo.Id.Equals(localTimeZoneId))
{
m_localTimeZone = timeZoneInfo;
break;
}
}
if (m_localTimeZone == null)
{
m_logger.Error(LogTopicEnum.AMR, "Could not find time zone with id: " + localTimeZoneId + " . will use default time zone (UTC).");
m_localTimeZone = TimeZoneInfo.Utc;
}

Optimal way to cache time of day description

What is the best method to cache the following? I am creating an intranet web application template that will display the message, e.g., Good Morning, Justin Satyr! near the top of my master page header. Obviously, I will have to determine whether to show Morning, Afternoon or Evening. For clarity, my code is below:
string partOfDay;
var hours = DateTime.Now.Hour;
if (hours > 16)
{
partOfDay = "evening";
}
else if (hours > 11)
{
partOfDay = "afternoon";
}
else
{
partOfDay = "morning";
}
I do not want to re-determine this on each page load because that seems moderately redundant and because I have to poll a SQL server to retrieve the user's full name. What is the best way to cache this information? If I cache it for the length of the session, then if the user begins using the application at 11:00 AM and finishes at 3:00 PM, it will still say Good Morning.
Is the best thing to do simply re-determine the M/A/E word each page load and cache the person's full name for the session? Or is there a better way?

I would just keep the user name in the Session object, the rest honestly is not worth caching and checking if it is out of date etc., just re-run it on each page - provided you put the implementation into a common library /class so you keep your code DRY.

In my opinion there is absolutely no need to cache the part of day. User information can be made available in the Session.

If you are talking in ASP.NET MVC context, you can use System.Web.Helpers namespace, where you can find WebCache helper. Than you need to calculate minutes to time of day_time will be changed and call WebCache.Set method with paramters: value="your string", minutesToCache=calculated_value.

Old, I know, but I don't cache mine, due to the obvious reason that the users time may change during the session. I store their calculated time in my session (calculates based on their timezone), and then use this code at the top of all pages:
<strong>#string.Format("Good {0}, ", SessionManager.GetUserCurrentDate().Hour > 16 ? "Evening" : SessionManager.GetUserCurrentDate().Hour > 11 ? "Afternoon" : "Morning") + SessionManager.GetDisplayName())</strong>
Works well for me!

How to count the data sent or received by my PC (all processes/programs)?

I need to count the amount (in B/kB/MB/whatever) of data sent and received by my PC, by every running program/process.
Let's say I click "Start counting" and I get the sum of everything sent/received by my browser, FTP client, system actualizations etc. etc. from that moment till I choose "Stop".
To make it simpler, I want to count data transferred via TCP only - if it matters.
For now, I got the combo list of NICs in the PC (based on the comment in the link below).
I tried to change the code given here but I failed, getting strange out-of-nowhere values in dataSent/dataReceived.
I also read the answer at the question 442409 but as I can see it is about the data sent/received by the same program, which doesn't fit my requirements.

Perfmon should have counters for this type of thing that you want to do, so look there first.

Alright, I think I've found the solution, but maybe someone will suggest something better...
I made the timer (tested it with 10ms interval), which gets the "Bytes Received/sec" PerformanceCounter value and adds it to a global "temporary" variable and also increments the sum counter (if there is any lag). Then I made second timer with 1s interval, which gets the sum of values (from temporary sum), divides it by the counter and adds to the overall amount (also global). Then it resets the temporary sum and the counter.
I'm just not sure if it is right method, because I don't know, how the variables of "Bytes Received/sec" PerformanceCounter are varying during the one second. Maybe I should make some kind of histograph and get the average value?
For now, downloading 8.6MB file gave me 9.2MB overall amount - is it possible the other processes would generate that amount of net activity in less than 20 seconds?