Connecting two classes?

Question

I'm trying to create a system that allows you to create a hospital ward and then add patients with personal details to each ward. The intention is being able to read all information from a single text/csv file.

I currently have the code to create patients and add their details but creating a ward and assigning patients to the ward is beyond my grasp. My lecturer suggested using an array of Patients as a property in the Ward class but its beyond my comprehension at the moment. A typical Patient would be written in my textfile as ''JoeBloggs,28,03/03/1989,8'' And the below code sorts the attributes etc.

Here is my current code to create patients:

 private void btnLoad_Click(object sender, RoutedEventArgs e)
    {
        //read files from file
        string[] patientList = File.ReadAllLines("MyList.txt");
        string[] patientArray = new string[4];
        string patientLong, name;
        Patient patient;
        int age, blood;
        DateTime dob;
        .

        for (int i = 0; i < patientList.Length; i++)
        {
            patientLong = patientList[i];//one long string with commas eg johnmurphy,22,12/9/1998,6
            patientArray = patientLong.Split(',');//split array according to comma
            name = patientArray[0];
            age = Convert.ToInt32(patientArray[1]);
            dob = DateTime.Parse(patientArray[2]);
            blood = Convert.ToInt32(patientArray[3]);


            patient = new Patient(name,age,dob,blood);
            bookList.Add(patient);

        }

       // lbxExpenses.ItemsSource = null;
        lstPatients.ItemsSource = patientList;
    }

And class Ward

class Ward
{
    public string Name { get; set; }

    public Patient [] Patient { get; set; }//array of patients as a property?

    public Ward(string name,int patient )
    {
        Name = name;
        Patient = new int[i];//currently giving error
    }

    public string GetWardDetails()
    {
        return string.Format("{0}", Name);
    }
}

Answer 1

The solution isn't to use an array, but instead, to use a generic list.

class Ward
{
    public string Name { get; set; }

    public List<Patient> Patients { get; set; }//array of patients as a property?

    public Ward(string name)
    {
        Name = name;
        Patients = new List<Patient>();
    }

    public string GetWardDetails()
    {
        return string.Format("{0}", Name);
    }
}

Now, when you would like to add or remove a Patient from the ward, you would do this:

Ward ward = new Ward("Emergency");
ward.Patients.Add(/*a valid patient object*/);

If you wanted to remove

ward.Patients.Remove(/*An already-existing patient object in the ward*/);

Some more about Lists can be found here. The problem is that arrays don't resize, while Lists do. So when you're reading a file, you can add new patients to the ward whenever you feel like. Also when you're instantiating a new object, you want to instantiate that object as its type. When you did = new int[0], you were telling it to assign type Patient to be an int, when it does not have the fields/properties in it to possibly be of type int. That's not to say you'll never assign one type to a different one, but you'll generally only do that if you want to achieve polymorphism.

If you wished to continue to use an array, you would have to do something along the lines of this:

class Ward
{
    public string Name { get; set; }

    public Patient[] Patients { get; private set; }

    public Ward(string name, IEnumerable<Patient> Patients)
    {
        Name = name;
        this.Patients = Patients.ToArray();
    }

    public Ward(string name, Patient[] Patients)
    {
        Name = name;
        Patients = Patients;
    }

    public string GetWardDetails()
    {
        return string.Format("{0}", Name);
    }
}

Cheers mate :)