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using System;
using System.Collections.Generic;
namespace TestCode
{
public class CountryCollection
{
static List<Country> db;
static CountryCollection()
{
db = new List<Country>();
db.Add(new Country(1, "Poland", "Warsaw", 38116000.0));
db.Add(new Country(2,"Portugal", "Lisbon", 10617575.0));
db.Add(new Country(3,"Australia", "Canberra", 21468700.0));
db.Add(new Country(4,"Austria", "Vienna", 8316487.0));
db.Add(new Country(5,"Belgium", "Brussels", 10666866.0));
db.Add(new Country(6,"Brazil", "Brasilia", 190132630.0));
db.Add(new Country(7,"China", "Bejing", 1321000000.0));
db.Add(new Country(8,"Chad", "N'Djamena", 10780600.0));
db.Add(new Country(9,"Venezuela", "Caracas", 28199822.0));
db.Add(new Country(10,"Vietnam", "Hanoi", 86116559.0));
db.Add(new Country(11,"New Zealand", "Wellington", 4268000.0));
db.Add(new Country(12,"Nigeria", "Abuja", 148000000.0));
db.Add(new Country(13,"Oman", "Muscat", 2577000.0));
db.Add(new Country(14,"Quatar", "Doha", 1450000.0));
db.Add(new Country(15,"Denmark", "Copenhagen", 5505995.0));
db.Add(new Country(16,"Dominican Republic", "Santo Domingo de Guzman", 9904000.0));
db.Add(new Country(17,"France", "Paris", 64473140.0));
db.Add(new Country(18,"United States of America", "Washington", 305619000.0));
db.Add(new Country(19,"Latvia", "Riga", 2270700.0));
}
public List<Country> GetCountries(string sortExpression)
{
var ret = new List<Country>();
ret.AddRange(db);
ret.Sort(new CountryComparer(sortExpression));
return ret;
}
public int Update(int id, string name, string capital, double population)
{
if (String.IsNullOrEmpty(name))
return 0;
int updated = 0;
foreach (Country c in db)
{
if (c.ID != id)
continue;
updated++;
c.Name = name;
c.Capital = capital;
c.Population = population;
}
return updated;
}
public int Insert(int id, string name, string capital, double population)
{
if (String.IsNullOrEmpty(name))
return 0;
db.Add(new Country(id, name, capital, population));
return 1;
}
public int Delete(int id)
{
var toDelete = new List<Country> ();
foreach (Country c in db)
{
if (c.ID != id)
continue;
toDelete.Add(c);
}
foreach (Country c in toDelete)
db.Remove(c);
return toDelete.Count;
}
}
sealed class CountryComparer : IComparer<Country>
{
string sortProperty;
bool descending;
public CountryComparer(string sortExpression)
{
descending = sortExpression.ToLowerInvariant().EndsWith(" desc");
if (descending)
{
sortProperty = sortExpression.Substring(0, sortExpression.Length - 5);
}
else
{
if (sortExpression.ToLowerInvariant().EndsWith(" asc"))
sortProperty = sortExpression.Substring(0, sortExpression.Length - 4);
else
sortProperty = sortExpression;
}
}
public int Compare(Country a, Country b)
{
int retVal = 0;
switch (sortProperty)
{
case "Name":
retVal = String.Compare(a.Name, b.Name, StringComparison.InvariantCultureIgnoreCase);
break;
case "Capital":
retVal = String.Compare(a.Capital, b.Capital, StringComparison.InvariantCultureIgnoreCase);
break;
case "Population":
retVal = (int)(a.Population - b.Population);
break;
}
if (descending)
return retVal;
return retVal * -1;
}
}
}