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how to format string to hh:mm:ss?

I am trying to make a digital clock in C#. I have 3 counter objects for hours, minutes and seconds. It has to be in format hh:mm:ss.
What I managed to do
String hours = _hours.Value.ToString();
String minutes = _minutes.Value.ToString();
String seconds = _seconds.Value.ToString();
if (hours.Length == 1)
{
hours = "0" + hours;
}
if (minutes.Length == 1)
{
minutes = "0" + minutes;
}
if (seconds.Length == 1)
{
seconds = "0" + seconds;
}
return hours + ":" + minutes + ":" + seconds;
It works but I am trying for a more efficient way of doing it using String.format. I have tried few different regular expressions but have been unsuccessful.
string b = string.Format("{0:D2}:{1:00}:{2:d2}", hours, minutes, seconds);
Cheers

Have you tried converting the string into int, before trying your string.Format? Something like below
string.Format("{0:00}:{1:00}:{2:00}",
int.Parse(hours), int.Parse(minutes), int.Parse(seconds));
If _hours.Value, _minutes.Value and _seconds.Value are numeric types, then you can use the below code which is more efficient
string.Format("{0:00}:{1:00}:{2:00}",
_hours.Value, _minutes.Value, _seconds.Value);

You can always try something a bit different:
DateTime dt = new DateTime(2000, 1, 1, hours, minutes, seconds); // just ignore year, month and day
var x = dt.ToString("HH:mm:ss");

IMO if you already have a string type it's useless to cast it to int or DateTime just to stringify it again after that.
I would use String.PadLeft method :
string h = hours.PadLeft(2, '0');
string m = minutes.PadLeft(2, '0');
string s = seconds.PadLeft(2, '0');
string result = h + ":" + m + ":" + s;
PadLeft will make your string to always have length at least of the value passed as a first parameter ( 2 in this case ) and fill "empty" places with the value passed in second parameter ( 0 in this case ).
Check this online

You can use the formatting options available on the ToString() method of DateTime like below:
(new DateTime(1900, 1, 1, _hours.Value, _minutes.Value, _seconds.Value)).ToString("HH:mm:ss");

You can try using:
string b = DateTime.Now.ToString("HH:mm:ss");

If you have some date variable, you can do so:
string b = dateVar.ToString("HH:mm:ss");
If you want solution exactly for your example, then:
return string.Format("{0:00}:{1:00}:{2:00}",
int.Parse(hours),
int.Parse(minutes),
int.Parse(seconds)
);

Convert DateTime (TimePart) to a readable days, hours and minutes based on a day hour

I have a code in c# and I need to accumulate all the hours in a DateTime format.
I have a foreach statement where I calculate pending hours but that pending hours need to be accumulated so at the end I have a total of hours and minutes and based on a day limit hours for example my day could be a 8 hours day, then I can format it as string like the following example:
If my total hours is: 24 hours 31 minutes then based on a 8 hour day I should format as follows:
3 days, 31 minutes.
I need to know the best way to accumulate the hours, here is the code that is inside my foreach:
// here I create a Timespan in order to get hours and minutes from a DB.
var timeSpan = TimeSpan.FromHours(double.Parse(drItem["PayableHours"].ToString()));
int hh = timeSpan.Hours;
int mm = timeSpan.Minutes;
int ss = timeSpan.Seconds;
// pending hours
// here i create a tempHours variable for a 8 hour
DateTime tempHours = new DateTime(1900, 1, 1, 8, 0, 0);
// here I substract from my 8 hour datetime the hours and the minutes of my timespan
DateTime pendingHours = dayHours.Add(new TimeSpan(-hh,-mm,0));
// here i should accumulate the pendingHours so when the foreach statement finish I can format the total hours and minutes to string.
Any clue?

From what I understand, it would look something like this:
private static string PrettyPrint(TimeSpan timeSpan)
{
var parts = new List<string>();
int totalHours = (int)timeSpan.TotalHours;
int workDays = totalHours / 8;
int remainingHours = (int)timeSpan.TotalHours - 8 * workDays;
if (workDays == 1) parts.Add("1 day");
if (workDays > 1) parts.Add(workDays + " days");
if (remainingHours == 1) parts.Add("1 hour");
if (remainingHours > 1) parts.Add(timeSpan.Hours + " hours");
if (timeSpan.Minutes == 1) parts.Add("1 minute");
if (timeSpan.Minutes > 1) parts.Add(timeSpan.Minutes + " minutes");
return string.Join(", ", parts);
}
You might want to also add some code to check for TimeSpan.Zero.

If I understand your question correctly, then:
int numberDays = hh / 8;
will give you the number of days. From there, the rest should be easy.

Rounding up a time to the nearest hour

ok basically I have a program that is re-writing text files and formatting them through various conditions, one of the conditions is that the date and time values in my original text file needs to be removed from its current location and moved into a new column I have created, this is done with the code below. I used a regex to find the date and time format and then remove it from its current location and store the value in a variable that I can use later...
if (line.Contains(date))
{
string pattern = #"(\d{2}:\d{2}:\d{2}\s?\d{2}/\d{2}/\d{4})";
string input = line;
string replacement = "";
Regex rgx = new Regex(pattern);
date1 = rgx.Match(input).ToString();
string result = rgx.Replace(input, replacement);
line = result;
}
This new value that is returned gets both the time and date values but only as one string, so I then used a split (shown below) to get the two values separate, now split[0] is my time variable (00/00/00 format) - which I now need to round up to the nearest hour. I am really not sure how to go about this, any ideas ?
string[] split = date1.Split(' ');
writer.WriteLine(split[0] + "\t" + split[1] + "\t" + line);

Get that date from the string into a DateTime struct. See for example the TryParseExact method
Then you can create a new DateTime value, based on year/month/day/hour of the value from the previous step, setting the minute and second parts to zero (see here )
Add one hour if the minutes or seconds part (of your first value) is not zero, using .AddHours(1), which returns a new DateTime value.
EDIT
Some sample code:
string inputdate = "2:56:30 8/7/2014";
DateTime dt;
System.Globalization.CultureInfo enUS = new System.Globalization.CultureInfo("en-US");
if (DateTime.TryParseExact(inputdate, "H:m:s d/M/yyyy", // hours:minutes:seconds day/month/year
enUS, System.Globalization.DateTimeStyles.None, out dt))
{
// 'dt' contains the parsed date: "8-7-2014 02:56:30"
DateTime rounded = new DateTime(dt.Year, dt.Month, dt.Day, dt.Hour, 0, 0);
if (dt.Minute > 0 || dt.Second > 0) // or just check dt.Minute >= 30 for regular rounding
rounded = rounded.AddHours(1);
// 'rounded' now contains the date rounded up: "8-7-2014 03:00:00"
}
else
{
// not a correct date
}

In my case, I need to round it to lower hour, and I used this logic:
DateTime x = new DateTime();
x = x.Date.AddHours(x.Hour);

You can try one liner solution to convert your DateTime to nearest hour,
//Input DateTime
DateTime input = DateTime.ParseExact("28/05/2021 2:16 PM", "dd/MM/yyyy h:mm tt", CultureInfo.InvariantCulture);
//Ternary Operation
var output = input.Minute > 30 //Check if mins are greater than 30
? input.AddHours(1).AddMinutes(-input.Minute) //if yes, then add one hour and set mins to zero
: input.AddMinutes(-input.Minute); //otherwise set mins to zero
Console.WriteLine(result.ToString());
Try Online: .NET Fiddle

Can you convert the string to a datetime?
Something like:
dateVariable = Convert.ToDateTime(dateString);
int hour = dateVariable.Hour;
int minute = dateVariable.Minute;
And then do the rounding.

Now as you have
string[] str = split[1].Split('/');
// create a new DateTime
int minutes = int.Parse(str[1]);
if(minutes >= 30)
hour = int.Parse(str[0]) + 1 // make sure if it 13 or 25 make it 1
minutes = 0 ;
sec = 0;
else {
hour = int.Parse(str[0]);
minutes = 0 ;
sec = 0 ;
}
var myDate = new Date(Year, month , day , hour , minutes , sec);

In C#
var Now = DateTime.Now;
var Nearest = Now.Date;
Nearest = Nearest.AddHours(Now.Hour + (Now.Minute >= 30 ? 1 : 0));
Now = Current time
Nearest = Rounded to the nearest hour

show timespan values after changed into local time

Our db server is outside of the country.. So i stored the created date using TimeZoneInfo like following,
DateTime dateTime = DateTime.Now;
var timeZone = TimeZoneInfo.ConvertTimeBySystemTimeZoneId(dateTime, TimeZoneInfo.Local.Id, "India Standard Time");
In page, i am showing used by Timespan. I create separate class for that..
My code
public static string GetFriendlyDate(DateTime dateTime)
{
TimeSpan ts = DateTime.Now.Subtract(dateTime);
string friendlyDate = dateTime.ToShortDateString();
int totalDays = (int)System.Math.Round(ts.TotalDays);
int totalHours = (int)System.Math.Round(ts.TotalHours);
int totalMinutes = (int)System.Math.Round(ts.TotalMinutes);
int totalSeconds = (int)System.Math.Round(ts.TotalSeconds);
int totalMilliSeconds = (int)System.Math.Round(ts.TotalMilliseconds);
int totalMonths = totalDays / 31; //approx.. change this
int totalYears = totalDays / 365; //approx.. change this
if (totalYears > 0) //give in terms of years
{
if (totalYears == 1)
friendlyDate = "last year";
else
friendlyDate = totalYears + " years ago";
}
else if (totalMonths > 1) //give in terms of months
{
if (totalMonths == 1)
friendlyDate = "last month";
else
friendlyDate = totalMonths + " months ago";
}
else if (totalDays > 1) //give in terms of days (at least 2 days)
{
friendlyDate = totalDays + " days ago";
}
else if (totalHours > 0) //give in terms of hours
{
if (totalHours == 1)
friendlyDate = "1 hour ago";
else
friendlyDate = totalHours + " hours ago";
}
else if (totalMinutes > 0) // give in terms of minutes
{
if (totalMinutes == 1)
friendlyDate = "1 minute ago";
else
friendlyDate = totalMinutes + " minutes ago";
}
else if (totalSeconds > 0) //give in terms of seconds
{
if (totalSeconds == 1)
friendlyDate = "1 second ago";
else
friendlyDate = totalSeconds + " seconds ago";
}
else //just now
{
friendlyDate = "a moment ago";
}
return friendlyDate;
}
when i run local it shows correctly "--seconds ago"... like that.. But in server it is always showing a moment ago, after some hours it is taking "---hours ago" like that..
can anyone please help me out of this problem?

If i want to get a correct way what i asked my question, i have to convert the time into UTC.
so i changed that..
var utcTime = DateTime.UtcNow.AddHours(5).AddMinutes(30);
TimeSpan ts = utcTime.Subtract(dateTime);
Now the issues is solved...

You were storing items as of India Standard Time, and then comparing them against the local time.
The solution you gave in your answer is adjusting the time back to India Standard Time, which is fixed at +5:30 offset from UTC. This only works because IST does not have any daylight saving time rules. If you were using a different time zone, such as US Eastern Time, it would not work reliably.
The correct solution is to store the original value as UTC. Instead of using DateTime.Now and converting to IST, just use DateTime.UtcNow and store the value directly. When you compare in your GetFriendlyDate method, you should also use DateTime.UtcNow as the basis for comparison.
If you already have data saved in your database in India Standard Time, then you will need to update those values when you make this change. For example, if this is SQL Server, you could run the following script to update your values from IST to UTC:
UPDATE mytable SET thedatetime = DATEADD(minute, -330, thedatetime)
In general, local date/time values such as those retrieved from DateTime.Now have no business being in a web application. Read The Case Against DateTime.Now.

Calculate time different between PM and AM in c# windows phone 7

I am trying to calculate time difference in PM and AM.
I have data of Monday 1:01 PM and tuesday 1:00AM.
I used below code to calculate the time difference.
And the result i get is:
-12 hour and -1 minutes
How should i go about doing it getting the correct time difference?
Below is the code:
if ((dayNow == "Monday") && (tues == "True"))
{
DateTime timeNow = DateTime.ParseExact(DateTime.Now.ToShortTimeString(),
"h:mm tt", new DateTimeFormatInfo());
DateTime timeSelected = DateTime.ParseExact(timePicker.ValueString,
"h:mm tt", new DateTimeFormatInfo());
TimeSpan timeLeft = timeSelected.Subtract(timeNow);
if (timeSelected > timeNow)
{
string hour = timeLeft.Hours.ToString();
string minute = timeLeft.Minutes.ToString();
string timeDifference = "This alarm is set for " + "1 day and "
+ hour + " hour and " + minute + " minutes from now.";
MessageBox.Show(timeDifference, "Alarm", MessageBoxButton.OK);
NavigationService.Navigate(new Uri("/listOfAlarm.xaml?",
UriKind.Relative));
}
else if (timeSelected < timeNow)
{
string hour = timeLeft.Hours.ToString();
string minute = timeLeft.Minutes.ToString();
string timeDifference = "This alarm is set for " + hour +
" hour and " + minute + " minutes from now.";
MessageBox.Show(timeDifference, "Alarm", MessageBoxButton.OK);
NavigationService.Navigate(new Uri("/listOfAlarm.xaml?",
UriKind.Relative));
}
else
{
NavigationService.Navigate(new Uri("/listOfAlarm.xaml?",
UriKind.Relative));
}
}

Bit Late to the show, but here is what I did.
An If statement, that figures out whether the time you have selected is greater than, or less than. If it is less than, then it will automatically add 24 hours to compensate, thus removing the negative sign and compensating for the program.
I converted the times to Integers, and then did this:
if (timeSelected > timeNow)
{
int_hour = Convert.ToInt16(hour); // Convert the string to integer
}
else
{
int_hour = Convert.ToInt16(hour) + 24; // Convert the string to integer ( Compensates for Negative)
}

Does replacing:
TimeSpan timeLeft = timeSelected.Subtract(timeNow);
with
TimeSpan timeLeft = timeNow.Substract(timeSelected);
fix your problem?