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How can i translate string timestamp to Date?

I has in string format, timestamp 1593339378252, i need convert this, to a normal human date-20.06.2020
I try this code
var timestamp = Convert.ToInt64(dateFrom);
// Format our new DateTime object to start at the UNIX Epoch
System.DateTime dateTime = new System.DateTime(1970, 1, 1, 0, 0, 0, 0);
// Add the timestamp (number of seconds since the Epoch) to be converted
dateTime = dateTime.AddSeconds(timestamp);
but if i try convert to int32,16,64 i get System.ArgumentOutOfRangeException

It seems that your timestamp actually contains number of milliseconds, not seconds:
new DateTime(1970,1,1,0,0,0,0,System.DateTimeKind.Utc).AddMilliseconds(1593339378252)
// on my machine - 28-Jun-20 10:16:18 AM

You can use var dateTimeOffset = DateTimeOffset.FromUnixTimeMilliseconds(yourValue);
For more information, also look at the documentation

Converting the date within the places.sqlite file in Firefox to a DateTime

I am having some trouble converting a date found in the file that stores browser history to a normal DateTime.
The file is located at: C:\Users[username]\AppData\Roaming\Mozilla\Firefox\Profiles[profilename]\places.sqlite
The table in question is: [moz_places]
The column is: [last_visit_date]
I've tried using the unix epoch and webkit format(like chrome uses), but neither are giving me the results I expect.
Here is my Unix conversion(not working):
public static DateTime FromUnixTime(long unixTime)
{
var epoch = new DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc);
return epoch.AddSeconds(unixTime);
}
This is my webkit conversion code: (Also not working for these dates, it works with chromes webkit dates)
public static DateTime ConvertWebkitTimeToDateTime(long ticks)
{
//Set up a date at the traditional starting point for unix time.
DateTime normalDate = new DateTime(1970, 1, 1, 0, 0, 0, 0);
//Subtract the amount of seconds from 1601 to 1970.
long convertedTime = (ticks - 11644473600000000);
//Devide by 1000000 to convert the remaining time to seconds.
convertedTime = convertedTime / 1000000;
//Add the seconds we calculated above.
normalDate = normalDate.AddSeconds(convertedTime);
//Finally we have the date.
return normalDate;
}
So what's the deal with these dates Firefox is storing? Here are a couple sample dates that should all be around today's date or yesterday's.(about 10/17/2013)
1373306583389000
1373306587125000
1373306700392000
Any help or documentation links would be awesome, thanks.

Unix timestamps are measured in seconds.
These values are larger by a factor of one million, i.e., they are using microseconds:
> select datetime(1373306583389000 / 1000000, 'unixepoch');
2013-07-08 18:03:03

Solution in C#:
public static DateTime FromUnixTime(long unixTime)
{
unixTime = unixTime / 1000000;
var epoch = new DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc);
return epoch.AddSeconds(unixTime);
}
CL. was correct in that this is simply the millisecond value from the Unix epoch.
Solution in SQL:
Here is a resource that explains his solution in greater detail:
https://support.mozilla.org/en-US/questions/835204

Converting ticks to DateTime

There are a number of questions on this site explaining how to do this. My problem I when I do what seems to work for everyone else I don't get the correct date or time. The code is ...
long numberOfTicks = Convert.ToInt64(callAttribute);
startDateTime = new DateTime(numberOfTicks);
The value of callAttribute is = "1379953111"
After converting it the value of numberOfTicks = 1379953111
But the DateTime ends up being startDateTime = {1/1/0001 12:02:17 AM}
I have taken the same value for ticks and converted it online and it comes up with the correct date/time.
What am I doing wrong?

Your value doesn't seem to be a number of ticks; I suspect it's a UNIX timestamp (number of seconds since 1970/01/01 UTC)
Here's a function to convert from a UNIX timestamp:
static readonly DateTime _unixEpoch =
new DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc);
public static DateTime DateFromTimestamp(long timestamp)
{
return _unixEpoch.AddSeconds(timestamp);
}

C# query datetime off sqlite database fails

I am reading a sqlite file in which datetime column data are saved as integer values (INTEGER NO NULL)
DateTime dt=reader.GetDateTime(nColDateTime);
But it emits an error saying that the return value is not in correct format.
I try out all other available methods in Datetime class and find only
DateTime dt=DateTime.FromBinary(reader.GetInt64(nColDateTime));
works (as others return exceptions).
But the formatted date (as dt.ToShortDateTime()) is incorrect (ie 0042/11/20) I have no idea what this is.
I then try this
long d=DateTime.Now.Ticks-reader.GetInt64(nColDateTime);
DateTime dt=new DateTime(d);
It gives me 1970/05/18
Could you help me to get the correct datetime ?

Your dates are stored in the Unix epoch format.
You probably just want to use:
private static readonly DateTime epoch = new DateTime(1970, 1, 1);
...
var myDate = epoch + TimeSpan.FromTicks(reader.GetInt64(nColDateTime));
For example, when I look at your example above "1970/05/18", I can assume that your date is approximately 5 months, 18 days earlier than today.
Here is how I would retreieve the original value:
(DateTime.Today - new DateTime(1970, 5, 18)).Ticks
Which returns:
13119840000000000
Plugging that into my formula:
new DateTime(1970, 1, 1) + TimeSpan.FromTicks(13119840000000000)
This returns:
2011/07/30

DateTime's representation in milliseconds?

I have a SQL-server timestamp that I need to convert into a representation of time in milliseconds since 1970. Can I do this with plain SQL? If not, I've extracted it into a DateTime variable in C#. Is it possible to get a millisec representation of this ?
Thanks,
Teja.

You're probably trying to convert to a UNIX-like timestamp, which are in UTC:
yourDateTime.ToUniversalTime().Subtract(
new DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc)
).TotalMilliseconds
This also avoids summertime issues, since UTC doesn't have those.

In C#, you can write
(long)(date - new DateTime(1970, 1, 1)).TotalMilliseconds

As of .NET 4.6, you can use a DateTimeOffset object to get the unix milliseconds. It has a constructor which takes a DateTime object, so you can just pass in your object as demonstrated below.
DateTime yourDateTime;
long yourDateTimeMilliseconds = new DateTimeOffset(yourDateTime).ToUnixTimeMilliseconds();
As noted in other answers, make sure yourDateTime has the correct Kind specified, or use .ToUniversalTime() to convert it to UTC time first.
Here you can learn more about DateTimeOffset.

There are ToUnixTime() and ToUnixTimeMs() methods in DateTimeExtensions class
DateTime.UtcNow.ToUnixTimeMs()

SELECT CAST(DATEDIFF(S, '1970-01-01', SYSDATETIME()) AS BIGINT) * 1000
This does not give you full precision, but DATEDIFF(MS... causes overflow. If seconds are good enough, this should do it.

This other solution for covert datetime to unixtimestampmillis C#.
private static readonly DateTime UnixEpoch = new DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc);
public static long GetCurrentUnixTimestampMillis()
{
DateTime localDateTime, univDateTime;
localDateTime = DateTime.Now;
univDateTime = localDateTime.ToUniversalTime();
return (long)(univDateTime - UnixEpoch).TotalMilliseconds;
}

Using the answer of Andoma, this is what I'm doing
You can create a Struct or a Class like this one
struct Date
{
public static double GetTime(DateTime dateTime)
{
return dateTime.ToUniversalTime().Subtract(new DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc)).TotalMilliseconds;
}
public static DateTime DateTimeParse(double milliseconds)
{
return new DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc).AddMilliseconds(milliseconds).ToLocalTime();
}
}
And you can use this in your code as following
DateTime dateTime = DateTime.Now;
double total = Date.GetTime(dateTime);
dateTime = Date.DateTimeParse(total);
I hope this help you