How to convert to datetime

Question

hi guys, I have a dropdownlist that displays time only.Like 8:00AM,8:30AM............When i save this time to database i want to save as todays date + time. eg:8:00AM as 03/30/2009 8:00:00:000.Can anybody give appropriate code to convert as above shown eg:

I tried Convert.ToDateTime(ddlStartTime.SelectedItem.Text) the one error is showing as "String was not recognized as a valid DateTime."

Answer 1

Read the parts of the time so you have hours and minutes, then use the following code:

DateTime myDate = DateTime.Now.Date;
myDate = myDate.AddHours(hours);
myDate = myDate.AddMinutes(minutes);

Answer 2

Have a look at DateTime.TryParse and DateTime.Today. Using them should be enough to do what you want.

Untested Code.

DateTime dt;
if (DateTime.TryParse(Dropdown1.SelectedValue, out dt))
{
    DateTime result = DateTime.Today.AddHours(dt.Hour).AddMinutes(dt.Minute);
}

Answer 3

Store as the value for each drop down item the number of minutes from midnight that the time represents. Then:-

valueToStore = DateTime.Today + TimeSpan.FromMinutes(Int32.Parse(value))

By storing using the value attribute of a HTML option to store a simple representation of the value you eliminate the codes dependancy on the actual format used to simply display the set of values. If it decided that the representation of the times be changed to use different format the rest of the code will continue to work unmodified.

Answer 4

var time = this.DropDownList1.SelectedValue.Split(':', ' ');
var hours = Int32.Parse(time[0]);
var minutes = Int32.Parse(time[1]);
var ampm = (time[2] == "PM") ? 12 : 0;
var dt = DateTime.Today.AddHours(hours + ampm).AddMinutes(minutes);

Parse your DropDownList for Hours and Minutes, then add them to DateTime.Today.

Answer 5

Basically, you just need to parse the time string. It will be automatically resolved to the current date.

Dim strTime As String = "8.30am"
Dim parsedTime As DateTime
If DateTime.TryParseExact(strTime, "h.mmtt", New System.Globalization.DateTimeFormatInfo(), Globalization.DateTimeStyles.None, parsedTime) = True Then
  'Parse was successful.
Else
  'Handle the error.
End If

Answer 6

Use ParseExact so that you can specify the format that you are using.

h = hours in 12-hour clock format
. = literal character
mm = minutes as two digits
tt = AM/PM designator

Dim time As DateTime = DateTime.ParseExact(dropdown.SelectedValue, "h.mmtt", CultureInfo.InvariantCulture)

The components of the DateTime value that you don't specify in the string (year, month, date, seconds, time zone, era) uses DateTime.Today as default, which is exactly what you want in this case.

Answer 7

VB.NET answer for Portmans Solution. Too many chars for comment so included here.

Dim time As String() = Me.DropDownList1.SelectedValue.Split(New Char() {":", " "})
Dim hours As Integer = Integer.Parse(time(0))
Dim minutes As Integer = Integer.Parse(time(1))
Dim ampm As Integer = 12
If time(2).ToLower() = "am" Then
  ampm = 0
End If
Dim dt As DateTime = DateTime.Today.AddHours(hours + ampm).AddMinutes(minutes)

Answer 8

This always seems to work for me. May not be the most elegant way, but I have not had any issues so far.

DateTime dTime = DateTime.Now;

string time = this.DropDownList1.SelectedValue;

DateTime FormattedDateTime = Convert.ToDateTime(dTime.Date.ToShortDateString() + " " + time);