0408-C#.txt

DateTime methods
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1. DateTime.Now   -- It returns "local" system datetime object
2. DateTime.UtcNow -- Returns "Universal Time (GMT)" DateTime object.


 Console.WriteLine(DateTime.Now);
 Console.WriteLine(DateTime.UtcNow);

3. Access DateTime parts using Day, Month, Hour etc...
 
  DateTime now = DateTime.Now;
  Console.WriteLine(now.Day); // 4
  Console.WriteLine(now.Hour); 

4. Create DateTime object with user defined date time.

   DateTime bdate = DateTime.Parse("12/31/2001 10:20:33 PM");
   //Or you can use TryParse() method.

   Console.Write(string.format(@"
{0}st {1} - {2} is my birth date ",bdate.Day, 
                                  bdate.ToString("MMMM"),
                                  bdate.Year));
  

5. Add days, hours, mins, year etc (Use negative value to subtract    days, hours etc).

    DateTime dt = DateTime.Now;
    Console.WriteLine("Current Date : " + dt);
    //Add five days to current date
    dt = DateTime.Now.AddDays(5);
    Console.WriteLine(dt);

    //add 10 years to current Date

    Console.WriteLine( DateTime.Now.AddYears(10) );

    //Subtract 100 days from current date

     Console.WriteLine ( DateTime.Now.AddDays(-100) );

EX: Display day name and year of 10 birthdates from 2012

    DateTime dt = DateTime.Parse("12/5/2012");
    
    for(int i=1;i<=10;i++)
    {
        dt = dt.AddYears(1);
        Console.WriteLine( dt.ToString("dddd - yyy"));
     }
   
6. Comparing DateTime objects

    int DateTime.Compare(dateObj1, dateObj2);

    It returns 0 if dateObj1 is equals to dateObj2
              >0 if dateObj1 is greater than dateObj2
              <0 if dateObj1 is less than dateObj2
Ex:
        DateTime dt1 = DateTime.Parse("12/6/2012 1 AM");
        DateTime dt2 = DateTime.Parse("12/6/2012");

        if (DateTime.Compare(dt1, dt2) > 0)
            Console.WriteLine("dt1 > dt2");
        else
            if (DateTime.Compare(dt1, dt2) < 0)
                Console.WriteLine("dt1 < dt2");
            else
                Console.WriteLine("dt1 eq dt2");

TimeSpan struct to find the differences in days, mins, secs or millis between two DateTime objects.
-------------------------------------------------------------------

    DateTime dt1 = DateTime.Parse("8/4/2013");
    DateTime dt2 = DateTime.Parse("8/1/2013");
    
    TimeSpan diff = dt1 - dt2;

    Console.WriteLine("Days : " + diff.TotalDays);
    Console.WriteLine("Hours : " + diff.TotalHours);