/**************************************************
* create a new customer in customer list
**************************************************/
private void addCustomerToList(int id, string name, int kwh)
{
// calculate cost based on radio box
if (radResidential.Checked == true) // residential customer
{
ResidentialCustomer cust = new ResidentialCustomer(id, txtCustomer.Text, 'R', kwh);
txtCost.Text = '$' + cust.Bill.ToString("f2"); // output to text box
custList.Add(cust);
}
else if (radCommercial.Checked == true) // commercial customer
{
CommercialCustomer cust = new CommercialCustomer(id, txtCustomer.Text, 'C', kwh);
txtCost.Text = '$' + cust.Bill.ToString("f2"); // output to text box
custList.Add(cust);
}
else if (radIndustrial.Checked == true) // industrial customer ... include off-peak hours
{
int offPeakKwh = 0;
// validate industrial off peak kWh
if (IsValidIndustrial())
{
offPeakKwh = Convert.ToInt32(txtOffPeak.Text); // get industrial off-peak hours from user
}
IndustrialCustomer cust = new IndustrialCustomer(id, txtCustomer.Text, 'I', kwh, offPeakKwh);
txtCost.Text = '$' + cust.Bill.ToString("f2"); // output to text box
custList.Add(cust);
}
// update listview
DisplayList(custList);
}
static string fpath = "customers.txt"; // the path to the file's location
/**************************************************
* reads from file to creates CustomerList
*************************************************/
public static List <Customer> LoadListFromFile()
{
FileStream fs;
StreamReader sr = null;
string line;
string[] fields;
int id;
string name;
char category;
decimal bill;
List <Customer> cl = new List <Customer>();
// try to read from file
try {
fs = new FileStream(fpath, FileMode.Open, FileAccess.Read);
sr = new StreamReader(fs);
while (!sr.EndOfStream) // while more customers
{
line = sr.ReadLine();
fields = line.Split(',');
id = Convert.ToInt32(fields[0]);
name = fields[1];
category = Convert.ToChar(fields[2]);
bill = Convert.ToDecimal(fields[3]);
// create customer type based on category
if (category == 'R')
{
ResidentialCustomer c = new ResidentialCustomer(id, name, category, bill);
cl.Add(c); // add to list
}
else if (category == 'C')
{
CommercialCustomer c = new CommercialCustomer(id, name, category, bill);
cl.Add(c);
}
else if (category == 'I')
{
IndustrialCustomer c = new IndustrialCustomer(id, name, category, bill);
cl.Add(c);
}
}
// handle exceptions
} catch (Exception ex) {
MessageBox.Show("Error while reading customer data \n" + ex.GetType().ToString() + ": " + ex.Message);
} finally {
if (sr != null)
{
sr.Close();
}
}
return(cl);
}