Dependency injection promotes loose coupling of components by passing dependencies to an object rather than having an object instantiate its own dependencies.(http://www.blackwasp.co.uk/DependencyInjection.aspx)
Example
public interface ITruck
{
void Go(double distance);
}
public class Truck : ITruck
{
public double Consumption{ get; set; }
public void Go(double distance)
{
double necessary_fuel = Consumption * distance;
}
}
public interface IRoute
{
void AddTruck(ITruck dependency);
}
public class Route : IRoute
{
ITruck _truck;
public double Distance { get; set; }
public void AddTruck(ITruck truck)
{
_truck = truck;
}
public void TruckGo()
{
_truck.Go(Distance);
}
}
Route route = new Route();
route.Distance = 100;
Truck truck = new Truck();
truck.Consumption = 20;
route.AddTruck(truck);
route.TruckGo();
