new to asp.net need help with creating a class

Hello i just started creating web forms, and i am really not clear on the concept of classes and delegates...what i 've been doing is in my code behind pages i add my methods in the event handlers and such and trypically i hadnt had the need to create a class and because i wasnt exactly clear about it i just avoided it.  But now i'm at the point where i dont want to be typing the same code into different handlers...so i have this code that i want to be public so i could access it from anywhere in the project...i read through articles tried to do it but im little lost...here is the code i want to be access
DateTime dt1 = new DateTime(DateTime.Now.Year, 1, 18); DateTime dt2 = new DateTime(DateTime.Now.Year, 9, 25); DateTime dt3 = new DateTime(DateTime.Now.Year, 10, 26); DateTime dt4 = new DateTime(DateTime.Now.Year, 4, 5); DateTime dt5 = new DateTime(DateTime.Now.Year, 6, 13); Dat ...