I have 14 textboxes that takes a user’s input of two times in a 24 hour clock format. When the calculate button is clicked the difference between the two times is calculated and returns the time in decimal format to the respective label. Ideally I would like the user to simply enter time as an integer, such as 1253 or 925 and select AM or PM from the drop down box. Say a user enters 1115 as the in time with AM selected then enters 300 as the out time with PM selected (as shown in the example entry below), the calculate button is clicked and 3.75 is returned in the label.
I have this code below and it works but I get errors when there aren’t exactly four characters. First question, how do I fix this so if an integer such as 800 will be read as 8:00 and not error out?
DateTime dt = DateTime.ParseExact(MondayW1InTextBox.Text, "HHmm", CultureInfo.InvariantCulture);
string timestring = dt.ToString("h:mm");
MondayW1Label.Text = timestring;
Second, once the string is formatted to 12 hour format, how can I get it to take the AM/PM drop down list as an argument for calculating the difference?
Below is the current C# code behind for just the Monday textboxes calculation which is just 24 hour time format, but want to move away from 24 hour time.
protected void CalculateButton_Click(object sender, EventArgs e)
{
TimeSpan TimeIn, TimeOut;
if (!TimeSpan.TryParse(MondayW1InTextBox.Text, out TimeIn)) TimeIn = default(TimeSpan);
if (!TimeSpan.TryParse(MondayW1OutTextBox.Text, out TimeOut)) TimeOut = default(TimeSpan);
MondayW1Label.Text = (TimeOut - TimeIn).TotalHours.ToString("f2");
}
Your first problem is related to the pattern you are using to parse the time: ParseExact will always try to match the exact pattern (in your case, "HHmm") to the string being parsed. That means it expects two digits representing the hours and two digits for the minutes. You can easily make it work if you append a leading zero to your string whenever its size is < 4. You can use the PadLeft method for doing that:
DateTime dt = DateTime.ParseExact(MondayW1InTextBox.Text.PadLeft(4, '0'), "HHmm", CultureInfo.InvariantCulture);
The first argument of PadLeft is the total length of the resulting string (in our case, 4), and the second argument is the character that should be used to fill in ('0').
For your second problem, you can parse the strings to get the DateTime object and, if the PM value is selected, just add 12 hours to the corresponding time.
DateTime timeIn = DateTime.ParseExact(MondayW1InTextBox.Text.PadLeft(4, '0'), "HHmm", CultureInfo.InvariantCulture);
DateTime timeOut = DateTime.ParseExact(MondayW1OutTextBox.Text.PadLeft(4, '0'), "HHmm", CultureInfo.InvariantCulture);
if(dropDownListIn.SelectedValue == "PM") timeIn = timeIn.AddHours(12);
if(dropDownListOut.SelectedValue == "PM") timeOut = timeOut.AddHours(12);
MondayW1Label.Text = (timeOut - timeIn).TotalHours.ToString("f2");
Notice that you can use the subtraction operator on DateTime objects to get the time difference between them, no need to explicitly convert them to TimeSpans.
Maybe this example (it is pretty crude but you get the logic) will be helpful:
string datetime1 = "800";
DateTime dt1 = DateTime.ParseExact((datetime1.Length == 3) ? "0" + datetime1 : datetime1, "hhmm", CultureInfo.InvariantCulture);
string dropDownVal = "AM";
if (dropDownVal == "PM")
dt1 = dt1.AddHours (12);
string datetime2 = "1100";
DateTime dt2 = DateTime.ParseExact((datetime2.Length == 3) ? "0" + datetime2 : datetime2, "hhmm", CultureInfo.InvariantCulture);
dropDownVal = "PM";
if (dropDownVal == "PM")
dt2 = dt2.AddHours (12);
TimeSpan TimeIn, TimeOut;
TimeIn = new TimeSpan (dt1.Ticks);
TimeOut = new TimeSpan(dt2.Ticks);
Console.WriteLine((TimeOut - TimeIn).TotalHours.ToString("f2"));
Console.ReadLine ( );
Related
Here's my code
DateTime TimeIn = "8:00 AM",
TimeOut="2:00 AM";
double Total;
private void compute()
{
Total = (TimeOut - TimeIn).TotalHours;
}
8:00am to 2:00am should result 18 hours.But mine is resulting -7
Another problem is when i typed 24:00 as time out C# couldn't recognize it as Time.
It works properly when the TimeOout is less than 12:00am. like 11:59pm backwards.
(eg.: 11:30PM - 8:00AM) it computes properly.
Please Help.
Add +24 hours when negative result.
may be this could help you:
string TimeIn= "8:00 AM";
string TimeOut= "2:00 AM";
TimeSpan duration = DateTime.Parse(TimeOut).Subtract(DateTime.Parse(TimeIn));
The way you have declared the datetime Value is wrong. The right way to do it is by converting the string to datetime format
DateTime TimeIn = Convert.ToDateTime("08:00");
DateTime TimeOut = Convert.ToDateTime("02:00");
TimeSpan ts = TimeIn - TimeOut;
If you need the 18 hours span that you're looking for you'll have to pass the date value as well while assigning data to the variables
i read a ini-file with a saved Date/Time string inside.
[Data]
Update = 07.02.2014 13:30:36
Rate_s = 5
I have both values as string in my C# program.
Now i want to save the "Update" in a value (Update_old) and the next time i read the file i want to check if Update_old+Rate_s >= Update_new
Means
The first time i read the file:
Update_old = 07.02.2014 13:30:36
Then 10 seconds later
Update_New = 07.02.2014 13:30:46
I need to know if the time changed.
My question is now how to convert the string with the date and time into something where i can add the 5secs and how to compare then the two values (old+rate against new)
It is possible that a new time is only 5seconds later but i can be also 1day 5hours later.
Thanks for the help
You need to parse the string values into a DateTime struct using DateTime.Parse. Then simply compare with <, >, ==, or !=
DateTime Update_New = DateTime.Parse("07.02.2014 13:30:36");
if (Update_New > Update_old)
{
}
If you want to manipulate the values use the AddX on the DateTime
Update_New = Update_New.AddSeconds(5);
Update_New = Update_New.AddHours(5);
Update_New = Update_New.AddDays(1);
If you parse both Update_old and Update_new into DateTimes, one of the possible results of subtraction of 2 date times is a TimeSpan, which conveniently has properties like TotalSeconds i.e.
if ((UpdateNewDateTime - UpdateOldDateTime).TotalSeconds > 5)
{ ...
However, if you are doing a lot of date manipulation, I would suggest you to also consider looking at NodaTime. This also takes into consideration issues with standard .Net DateTime like TimeZones, daylight savings, and inconsistencies in human calendars.
You can use DateTime.ParseExact to get a datetime and TimeSpan.FromSeconds to get a TimeSpan of 5 seconds.
string Update_old = "07.02.2014 13:30:36";
string Rate_s = "5";
DateTime oldDt = DateTime.ParseExact(Update_old, "dd.MM.yyyy HH:mm:ss", CultureInfo.InvariantCulture);
string Update_New = "07.02.2014 13:30:46";
DateTime newDt = DateTime.ParseExact(Update_New, "dd.MM.yyyy HH:mm:ss", CultureInfo.InvariantCulture);
TimeSpan seconds = TimeSpan.FromSeconds(int.Parse(Rate_s));
if (oldDt + seconds > newDt)
{
// ...
}
Side-note: instead of using ParseExact you can also use DateTime.Parse with the correct culture. In this case it could be german culture("de-DE"):
var deCulture = CultureInfo.CreateSpecificCulture("de-DE");
DateTime oldDt = DateTime.Parse("07.02.2014 13:30:36", deCulture);
DateTime newDt = DateTime.Parse("07.02.2014 13:30:46", deCulture);
Since it's a file i would not use DateTime.Parse without a culture because the current-culture could change.
convert string to datetime type;
DateTime start = (DateTime)strDateTime.toDate("dd.MM.yyyy H:mm:ss");
as Tim Schmelter said use TimeSpan to add period of time ( as an ex. 10 sec )
TimeSpan seconds = TimeSpan.FromSeconds(10);
and compare using operators <=, >=, ==, >, <.
I have TimeSpan data represented as 24-hour format, such as 14:00:00, I wanna convert it to 12-hour format, 2:00 PM, I googled and found something related in stackoverflow and msdn, but didn't solve this problem, can anyone help me? Thanks in advance.
Update
Seems that it's possible to convert 24-hour format TimeSpan to String, but impossible to convert the string to 12-hour format TimeSpan :(
But I still got SO MANY good answers, thanks!
(Summing up my scattered comments in a single answer.)
First you need to understand that TimeSpan represents a time interval. This time interval is internally represented as a count of ticks an not the string 14:00:00 nor the string 2:00 PM. Only when you convert the TimeSpan to a string does it make sense to talk about the two different string representations. Switching from one representation to another does not alter or convert the tick count stored in the TimeSpan.
Writing time as 2:00 PM instead of 14:00:00 is about date/time formatting and culture. This is all handled by the DateTime class.
However, even though TimeSpan represents a time interval it is quite suitable for representing the time of day (DateTime.TimeOfDay returns a TimeSpan). So it is not unreasonable to use it for that purpose.
To perform the formatting described you need to either rely on the formatting logic of DateTime or simply create your own formatting code.
Using DateTime:
var dateTime = new DateTime(timeSpan.Ticks); // Date part is 01-01-0001
var formattedTime = dateTime.ToString("h:mm tt", CultureInfo.InvariantCulture);
The format specifiers using in ToString are documented on the Custom Date and Time Format Strings page on MSDN. It is important to specify a CultureInfo that uses the desired AM/PM designator. Otherwise the tt format specifier may be replaced by the empty string.
Using custom formatting:
var hours = timeSpan.Hours;
var minutes = timeSpan.Minutes;
var amPmDesignator = "AM";
if (hours == 0)
hours = 12;
else if (hours == 12)
amPmDesignator = "PM";
else if (hours > 12) {
hours -= 12;
amPmDesignator = "PM";
}
var formattedTime =
String.Format("{0}:{1:00} {2}", hours, minutes, amPmDesignator);
Admittedly this solution is quite a bit more complex than the first method.
TimeSpan represents a time interval not a time of day. The DateTime structure is more likely what you're looking for.
You need to convert the TimeSpan to a DateTime object first, then use whatever DateTime format you need:
var t = DateTime.Now.TimeOfDay;
Console.WriteLine(new DateTime(t.Ticks).ToString("hh:mm:ss tt"));
ToShortTimeString() would also work, but it's regional-settings dependent so it would not display correctly (or correctly, depending on how you see it) on non-US systems.
TimeSpan represents a time interval (a difference between times),
not a date or a time, so it makes little sense to define it in 24 or 12h format. I assume that you actually want a DateTime.
For example 2 PM of today:
TimeSpan ts = TimeSpan.FromHours(14);
DateTime dt = DateTime.Today.Add(ts);
Then you can format that date as you want:
String formatted = String.Format("{0:d/M/yyyy hh:mm:ss}", dt); // "12.4.1012 02:00:00" - german (de-DE)
http://msdn.microsoft.com/en-us/library/az4se3k1%28v=vs.100%29.aspx
Try This Code:
int timezone = 0;
This string gives 12-hours format
string time = DateTime.Now.AddHours(-timezone).ToString("hh:mm:ss tt");
This string gives 24-hours format
string time = DateTime.Now.AddHours(-timezone).ToString("HH:mm:ss tt");
Assuming you are staying in a 24 hour range, you can achieve what you want by subtracting the negative TimeSpan from Today's DateTime (or any date for that matter), then strip the date portion:
DateTime dt = DateTime.Today;
dt.Subtract(-TimeSpan.FromHours(14)).ToShortTimeString();
Yields:
2:00 PM
String formatted = yourDateTimeValue.ToString("hh:mm:ss tt");
It is very simple,
Let's suppose we have an object ts of TimesSpan :
TimeSpan ts = new TimeSpan();
and suppose it contains some value like 14:00:00
Now first convert this into a string and then in DateTime
as following:
TimeSpan ts = new TimeSpan(); // this is object of TimeSpan and Suppose it contains
// value 14:00:00
string tIme = ts.ToString(); // here we convert ts into String and Store in Temprary
// String variable.
DateTime TheTime = new DateTime(); // Creating the object of DateTime;
TheTime = Convert.ToDateTime(tIme); // now converting our temporary string into DateTime;
Console.WriteLine(TheTime.ToString(hh:mm:ss tt));
this will show the Result as: 02:00:00 PM
Normal Datetime can be converted in either 24 or 12 hours format.
For 24 hours format - MM/dd/yyyy HH:mm:ss tt
For 12 hours format - MM/dd/yyyy hh:mm:ss tt
There is a difference of captial and small H.
dateTimeValue.ToString(format, CultureInfo.InvariantCulture);
If I have a date and time in a DateTime object, can I remove say 10 minutes, or 24 hours etc from the date and time using a format string?
So if I have 1/1/1990 12:30:00pm and I wanted to remove 1 hour from it, can I use a format string?
edit
i need to store diary entries and the user can select a reminder type. so 1 hour before hand. so then i'd like to store the format string in a db that i can get and apply to a datetime to get the reminder date time
Something like this might do what you need. Not sure what you mean by subtracting an hour using a format string though.
DateTime dt = new DateTime(1990, 1, 1, 12, 30, 0);
string s = dt.Subtract(new TimeSpan(1, 0, 0)).ToString("MM/dd/yyyy hh:mm:ss tt")
Best way is to convert to a DateTime object and then back to the formatted string (if that's what you need):
var time = DateTime.Parse("1/1/1990 12:30:00pm");
time = time.AddMinutes(-10);
string timeString = time.ToString("MM/dd/yyyy hh:mm:ss tt");
You can use this in your query if you have..
DATE_SUB(date,INTERVAL expr unit)
Example:
YourDate = DATE_SUB(1/1/1990 12:30:00pm, INTERVAL 1 HOUR)
YourDate = DATE_SUB(1/1/1990 12:30:00pm, INTERVAL 12 MINUTE)
YourDate = DATE_SUB(1/1/1990 12:30:00pm, INTERVAL 45 SECONDS)
I have the string "9:00 AM". I would like to get the offset from midnight as a TimeSpan in C#?
9:00 AM is a punctual time, while TimeSpan structure represents time intervals so you are trying to convert apples to oranges.
Timespan? A timespan is just a period of time. The "AM" shows that this is a specific time, so this cannot be a timespan. Or do you want to parse "9:00", without the "AM", and get a timespan of 9 hours as result?
#Your comment:
You could use a method that does this for you. Here's a simple example implementation (you would need to add better input validation, use better convert methods than just Convert.ToInt32() and so on):
public static TimeSpan GetTimeSpanFormString(string strString)
{
strString = strString.Trim();
string[] strParts = strString.Split(':', ' ');
int intHours, intMinutes;
if (strParts.Length != 3)
throw new ArgumentException("The string is not a valid timespan");
intHours = strParts[2].ToUpper() == "PM" ? Convert.ToInt32(strParts[0]) + 12 : Convert.ToInt32(strParts[0]);
intMinutes = Convert.ToInt32(strParts[1]);
return new TimeSpan(intHours, intMinutes, 0);
}
If you want the offset from midnight, you can use:
DateTime dateTime = DateTime.ParseExact( strValue, "h:mm tt" );
TimeSpan offset = dateTime - DateTime.Today;
TimeSpan.TryParse(yourString, out yourTimeSpan);