Question

   List<Customer> customers = new List<Customer>();
    int id = 0;
    int click = -1;

    public Form1()
    {
        InitializeComponent();
    }

    private void Form1_Load(object sender, EventArgs e)
    {

    }

    private void AddButton_Click(object sender, EventArgs e)
    {
        Customer rec1 = new Customer("C0020", "Alfred", "Campbelltown", 1500, 2006);
        Customer rec2 = new Customer("C0021", "Ryder", "Liverpool", 2000, 2008);
        Customer rec3 = new Customer("C0022", "Alison", "Strathfield", 5500, 2012);
        Customer rec4 = new Customer("C0023", "Eliza", "Liverpool", 6000, 2012);
        Customer rec5 = new Customer("C0024", "Natsu", "Campbelltown", 2560, 2011);

        customers.Add(rec1);
        customers.Add(rec2);
        customers.Add(rec3);
        customers.Add(rec4);
        customers.Add(rec5);

        click = customers.Count - 1;

    }

How do i calculate the total balance by particular suburb? I can calculate the total balance of everything by using the code below:

        double total = 0;

        foreach (Customer Total in customers)
            total += Total.Balance; //Total Balance

Any Ideas? thanks

Answer 1

In C# >= 3.5 simplest way will be using LINQ:

customers.Where(c => c.Suburb == "whatever").Sum(c => c.Balance);

Sorry, you didn’t describe your Customer props, so I’ve assumed them.