I want to display a "date/time submitted" value much the same way as Stack Overflow does
e.g.* 2 hours ago
* 3 days ago
* a month ago
I see extensive answers on how to do this in PHP but can someone help me with the VB version?
First calculate the exact time since submission:
Dim t As TimeSpan = DateTime.Now - submittedTime
Then you decide on what intervals you want to use for displaying the result. For example:
If t.TotalSeconds < 60 Then
display = "Less than a minute ago"
ElseIf t.TotalMinutes < 60 Then
display = t.Minutes.ToString() + " minutes ago"
ElseIf ...
... and so on
End If
All the way back on question 11, Jeff posted the code they use here on stackoverflow. It's in c#, but the conversion to vb.net should be pretty easy. There's heaps of other good suggestions in that question too.
Personally, I've used Sam Allen's code to get prettydates before. He modeled it off some code that John Resig wrote, so it's good quality stuff. Once again, c#, but it converts to vb.net pretty easily.
You need a DateTime structure
you simply substract [now] - [original message time] = difference time
you will need the DateTime.Substract method
What you're looking for is the TimeSpan structure. This structure stores a span of time (as the name suggests). It is the type returned when you subtract two DateTime structures
Dim start as DateTime = DateTime.Now
...
' Some time after the start
Dim span = DateTime.Now - start
I've posted a blog post to do just this. However it is in C#, but you can easily convert into vb.net
http://blog.nirandas.com/post/displaying-time-in-relative-format.aspx
Related
I have a clock on VB and i have got it to say the date and time but it wont show the milliseconds on the time.
time = DateTime.Now.ToString("dd/mm/yy HH:mm:ss")
So I know how to put the hours minuets and seconds but im not sure how to add milliseconds.
Please could someone help.
Thank You
Use fff to represent the milliseconds.
For example:
time = DateTime.Now.ToString("dd/mm/yy HH:mm:ss.fff")
See MSDN for the possible placeholders.
I am trying to calculate create a time remaining calculator in VB.NET and it won't let me and I can't seem to figure out why. Here is my code
Dim PrefendinedDateTime As DateTime = "3:00:00"
Dim TimeNow As DateTime = DateTime.Now
Dim ElapsedTime As TimeSpan = (TimeNow - frmStartDateTime)
Dim TimeRemaining As TimeSpan = PrefendinedDateTime - New DateTime(ElapsedTime.Ticks)
txtTimeRemaining.Text = New DateTime(TimeRemaining.Ticks).ToString("HH:mm:ss")
I get this error message:
Ticks must be between DateTime.MinValue.Ticks and DateTime.MaxValue.Ticks.
Parameter name: ticks
Not quite sure what this means
You cannot cast a timespan to a date, because those are different ticks. What you need is this:
txtTimeRemaining.Text = TimeRemaining.ToString("g")
or this:
txtTimeRemaining.Text = TimeRemaining.ToString("hh\:mm\:ss")
Notice how format string is different for TimeSpan, compared to formatting a date time, for example, and that : now requires escaping. This is explained in detail in below link #2.
References:
Standard TimeSpan Format Strings # MSDN
Custom TimeSpan Format Strings # MSDN
Let's stop here for a second, while I try to explain why it did not work for you. Forget about ticks, think in seconds, because it's a measurable interval, that's easy to get a grasp on. Suppose you time interval is a second. Now you are trying to create a date, passing one second into it. What do you expect to get? 1 second AD, i.e. 1st year, 1st month etc.? Fair enough.
Suppose now you have an interval of minus 1 second (yes, intervals can be negative). You would think it's 1 second BC, right? Unfortunately, negative dates in .NET are not allowed.
As a general rule of thumb, intervals of time (represented in .NET by a TimeSpan), and points in time (represented by a DateTime) should be treated separately, because they are logically different entities. There is one-way relation though, i.e. two dates can represent a TimeSpan. However, a TimeSpan does not represent two dates. In fact, no matter how many TimeSpans you have, you will never be able to relate them to any point in time.
I have spent quite a few hours and still unable to understand this:
Dim unix_time_at_midnight As Long
DateTime.DateFormat = "MM/dd/yyyy"
unix_time_at_midnight = DateTime.DateParse(DateTime.Date(unix_time*1000))/1000
where both unix_time_at_midnight and unix_time are long values. I understand DateTime.DateParse excepts a String and converts it to DateTime. What is (DateTime.Date(unix_time*1000))/1000 returning and what is its equivalent in Java? The requirement is to get the number of seconds since GMT midnight and I have successfully implemented it in Java. However, I would like to understand this particular line of code written in VB.net
EDIT: This method was written in Basic4Android and probably constitutes more of its libraries then vb.net. However, I have looked into each for details but unable to understand. Would appreciate if you could elaborate. Please see the links.
Take this:
DateTime.Date(unix_time*1000)
The documentation says:
Date (Ticks As Long) As String
Returns a string representation of the date (which is stored as ticks).
The date format can be set with the DateFormat keyword.
So that part returns a string representing the date.
It then uses DateTime.DateParse, which is documented as:
DateParse (Date As String) As Long
Parses the given date string and returns its ticks representation.
Taken together, this appears to take the ticks, multiplied by 1000, converted to a string that doesn't contain hour information which is parsed back to ticks which are divided by 1000.
The important thing to note is that the DateFormat set on the line before contains only the formatting for the date, no hours/minutes/seconds and smaller units of time exist in it. This means that the string returned essentially represents midnight of that date.
I have had a quick look around and I can't find an answer to this in vb.net or something that I can convert into vb.net.
I have two DateTimes in vb.net's 'Date' class. I would like to find the difference between these in seconds. I can do a-b, but the answer will still be a 'date'. I can use .seconds .minutes etc. and multiply but I will hit problems when I come to months.
Is there a simple way to do this, or do I need to write some elaborate-ish code?
Many Thanks
Subtract the DateTime values from each other - the returned type will be a TimeSpan.
Get the TotalSeconds value from it.
(date1 - date2).TotalSeconds
There actually is also a function made for this DateDiff(DateInterval.Second, d1, d2)
How about something like
Dim secs As Double = DateTime.Today.Subtract(DateTime.Today.AddDays(-1)).TotalSeconds
Look at DateTime.Subtract Method (DateTime) and TimeSpan.TotalSeconds Property
I am using these codes for displaying time in VB.NET
it shows up in 24 hours format besides i need it in 12 hours format
System.DateTime.Now.Hour
System.DateTime.Now.Minute
System.DateTime.Now.Second
example:
14:12:42
I need it as :
02:12:42
thanks.
Use String.Format. For example:
String.Format("{0:T}", System.DateTime.Now) //02:12:42 PM
String.Format("{0:hh:mm:ss}", System.DateTime.Now) //02:12:42
String.Format("{0:hh:mm:ss tt}", System.DateTime.Now) //02:12:42 PM
Also, this website to be very helpful in summarizing the various ways you can use String.Format. Keep in mind the culture can make a difference on non-custom formats. The first example above using T (Long Time format) works on my US-based PC just fine. But if you say:
String.Format(System.Globalization.CultureInfo.InvariantCulture, _
"{0:T}", System.DateTime.Now)
You end up with 14:12:42. The latter two examples are custom formats and are not affected by culture.
When using DateTime objects you can actually use the ToString() method and set your format inside it.
string currentTime = System.DateTime.Now.ToString("hh:mm:ss");
Check this msdn article out for more clarity:
http://msdn.microsoft.com/en-us/library/zdtaw1bw.aspx
Use the appropriate format string for display.
string formatted = myDateTime.ToString("hh:mm:ss");
I have used a custom format string in this case.
1-Use regex to get first two characters of that string ie from 23:11:59 get 23
2-convert this number to integer type
3-now check it if it is not greater than 12 and if it is subtract 12 from it and by using string.replace replace the old value.
Try This...
Dim CurTime As String
CurTime = TimeOfDay.ToString("h:mm:ss tt")