No clue about arrays, everything fails ...

I want to fill an array in the constructor of my object, and then use it in
in another method. But no matter what I try, I can't get this right. It is too different from how arrays used to be. Either it does not compile, or the array remains null as in the example below. How should I do it

class Calendar

{
private static int day,month;
private static int[] daysPerMonth;

public Calendar()
{
day=16;
daysPerMonth[1] = 31;
daysPerMonth[2] = 28;
daysPerMonth[3] = 31; // does not work, daysPerMonth remains null
// ...
}

public static AddDay()
{
day++;
if (day>daysPerMonth[month])
{month++; day=1;}
// ...
}

Regards,

Guido

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No clue about arrays, everything fails ...

Big_Show
Yes, that is what I was looking for, I think.
I didn't find it at first because it isn't called ArrayList but simply List.

Regards,

Guido
Pierre123
Thanks.

I will be changing the number of months, days etc. since it is a different world, so I can't use any Earth-based calendars.

This also means that specifying the length of the array in the declaration is something I would rather not do, since we could have a year with many more months than 12. The specifics will eventually be read from a file.

Regards,

Guido
brave43
ArrayList is in the System.Collections namespace. "using" this namespace will allow you access to the ArrayList class.
vitamin
If your arrays need to be that dynamic you might want to look at the ArrayList.
Raks
re: m_str = new string [size]

doesn't this come up with a compilation error "A constant value is expected"
Farooq Azam
You need to initialize the array, just like any other class:

private static int[] daysPerMonth = new int[12];

Note that the array index will start at 0.

PS: There're ready to use Calendar classes in the framework (in the System.Globalization namespace), and the DateTime class has a static method to calculate the number of days in any given month (it also requires a year argument to take leap years into account).
Haritvm
Not in C#. It would in C++.

.NET Developer

"The specifics will eventually be read from a file."

You can initalize the array size with a variable. IE:

class Tmp
class Tmp
{
  public string[] m_str;
  public Tmp(string thesize)
  {
   int size = Int32.Parse(thesize);
   m_str = new string[size];
   for(int i = 0; i < size; i++)
   {
    m_str[ i ] = i.ToString();
   }
  }

}

Watson How
thanks Matthew, I'd just had a mental block about how to define the array size this afternoon...bizarre.
No clue about arrays, everything fails ...

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