DateTime.ToFileTimeUtc() Method in C#

This method is used to convert the value of the current DateTime object to a Windows file time.

Syntax: public long ToFileTimeUtc ();

Return Value: This method returns the value of the current DateTime object expressed as a Windows file time.

Exception: This method will give ArgumentOutOfRangeException if the resulting file time would represent a date and time before 12:00 midnight January 1, 1601 C.E. UTC.

Below programs illustrate the use of DateTime.ToFileTimeUtc() Method:

Example 1:

// C# program to demonstrate the
// DateTime.ToFileTimeUtc()
// Method
using System;
using System.Globalization;

class GFG {

    // Main Method
    public static void Main()
    {
        try {

            // creating object of DateTime
            DateTime date = new DateTime(2011, 1,
                                    1, 4, 0, 15);

            // converting current DateTime object
            // to a Windows file time.
            // using ToFileTimeUtc() method;
            long value = date.ToFileTimeUtc();

            // Display the TimeSpan
            Console.WriteLine("Windows file time(UTC) "+
                                       "is {0}", value);
        }

        catch (ArgumentOutOfRangeException e)
        {
            Console.Write("Exception Thrown: ");
            Console.Write("{0}", e.GetType(), e.Message);
        }
    }
}

Output:

Windows file time(UTC) is 129383280150000000

Example 2: For ArgumentOutOfRangeException

// C# program to demonstrate the
// DateTime.ToFileTimeUtc()
// Method
using System;
using System.Globalization;

class GFG {

    // Main Method
    public static void Main()
    {
        try {

            // creating object of DateTime
            DateTime date = new DateTime(1600, 1,
                                    1, 4, 0, 15);

            // converting current DateTime
            // object to a Windows file time.
            // using ToFileTimeUtc() method;
            long value = date.ToFileTimeUtc();

            // Display the TimeSpan
            Console.WriteLine("Windows file time(UTC) is "+
                                             "{0}", value);
        }

        catch (ArgumentOutOfRangeException e)
        {
            Console.Write("Exception Thrown: ");
            Console.Write("{0}", e.GetType(), e.Message);
        }
    }
}

Output:

Exception Thrown: System.ArgumentOutOfRangeException

Reference:

• https://docs.microsoft.com/en-us/dotnet/api/system.datetime.tofiletimeutc?view=netframework-4.7.2