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Convert.ToDateTime Method (Object)

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Converts the value of the specified Object to a DateTime.

Namespace:  System
Assembly:  mscorlib (in mscorlib.dll)

Syntax

'Declaration
Public Shared Function ToDateTime ( _
    value As Object _
) As DateTime

public static DateTime ToDateTime(
    Object value
)

Parameters

Return Value

Type: System.DateTime
A DateTime equivalent to the value of value.
-or-
A DateTime equivalent to DateTime.MinValue if value is nulla null reference (Nothing in Visual Basic).

Exceptions

Exception Condition
FormatException

value is not a valid DateTime value.
InvalidCastException

value does not implement IConvertible.

-or-

The conversion is not supported.

Remarks

For the conversion to succeed, the runtime type of the value parameter must be either a DateTime or a String, or value must be nulla null reference (Nothing in Visual Basic). Otherwise, the method throws an InvalidCastException. In addition, if value is a string, it must contain a valid representation of a date and time value in the current culture or a FormatException is thrown.

The return value is the result of invoking the IConvertible.ToDateTime method of the underlying type of value.

Examples

The following example calls the ToDateTime(Object) method with a variety of Object variables.

Module Example
   Public Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)
      ' Try converting an integer.
      Dim number As Integer = 16352
      ConvertToDateTime(outputBlock, number)

      ' Convert a null.
      Dim obj As Object = Nothing
      ConvertToDateTime(outputBlock, obj)

      ' Convert a non-date string.
      Dim nonDateString As String = "monthly"
      ConvertToDateTime(outputBlock, nonDateString)

      ' Try to convert various dates.
      Dim dateString As String
      dateString = "05/01/1996"
      ConvertToDateTime(outputBlock, dateString)
      dateString = "Tue Apr 28, 2009"
      ConvertToDateTime(outputBlock, dateString)
      dateString = "06 July 2008 7:32:47 AM"
      ConvertToDateTime(outputBlock, dateString)
      dateString = "17:32:47.003"
      ConvertToDateTime(outputBlock, dateString)
   End Sub

   Private Sub ConvertToDateTime(ByVal outputBlock As System.Windows.Controls.TextBlock, ByVal value As Object)
      Dim convertedDate As Date
      Try
         convertedDate = Convert.ToDateTime(value)
         outputBlock.Text += String.Format("'{0}' converts to {1}.", value, convertedDate) & vbCrLf
      Catch e As FormatException
         outputBlock.Text += String.Format("'{0}' is not in the proper format.", value) & vbCrLf
      Catch e As InvalidCastException
         outputBlock.Text += String.Format("Conversion of the {0} '{1}' is not supported", _
                           value.GetType().Name, value) & vbCrLf
      End Try
   End Sub
End Module
' The example displays the following output:
'       Conversion of the Int32 '16352' is not supported
'       '' converts to 1/1/0001 12:00:00 AM.
'       'monthly' is not in the proper format.
'       '05/01/1996' converts to 5/1/1996 12:00:00 AM.
'       'Tue Apr 28, 2009' converts to 4/28/2009 12:00:00 AM.
'       '06 July 2008 7:32:47 AM' converts to 7/6/2008 7:32:47 AM.
'       '17:32:47.003' converts to 5/28/2008 5:32:47 PM.

using System;

public class Example
{
   private static System.Windows.Controls.TextBlock outputBlock;

   public static void Demo(System.Windows.Controls.TextBlock outputBlock)
   {
      Example.outputBlock = outputBlock;

      // Try converting an integer.
      int number = 16352;
      ConvertToDateTime(number);

      // Convert a null.
      object obj = null;
      ConvertToDateTime(obj);

      // Convert a non-date string.
      string nonDateString = "monthly";
      ConvertToDateTime(nonDateString);

      // Try to convert various date strings.
      string dateString;
      dateString = "05/01/1996";
      ConvertToDateTime(dateString);
      dateString = "Tue Apr 28, 2009";
      ConvertToDateTime(dateString);
      dateString = "06 July 2008 7:32:47 AM";
      ConvertToDateTime(dateString);
      dateString = "17:32:47.003";
      ConvertToDateTime(dateString);
   }

   private static void ConvertToDateTime(object value)
   {
      DateTime convertedDate;
      try
      {
         convertedDate = Convert.ToDateTime(value);
         outputBlock.Text += String.Format("'{0}' converts to {1}.", value, convertedDate) + "\n";
      }
      catch (FormatException)
      {
         outputBlock.Text += String.Format("'{0}' is not in the proper format.", value) + "\n";
      }
      catch (InvalidCastException)
      {
         outputBlock.Text += String.Format("Conversion of the {0} '{1}' is not supported",
                           value.GetType().Name, value) + "\n";
      }
   }
}
// The example displays the following output:
//       Conversion of the Int32 '16352' is not supported
//       '' converts to 1/1/0001 12:00:00 AM.
//       'monthly' is not in the proper format.
//       '05/01/1996' converts to 5/1/1996 12:00:00 AM.
//       'Tue Apr 28, 2009' converts to 4/28/2009 12:00:00 AM.
//       '06 July 2008 7:32:47 AM' converts to 7/6/2008 7:32:47 AM.
//       '17:32:47.003' converts to 5/28/2008 5:32:47 PM.

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Xbox 360, Windows Phone OS 7.0

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.