// Have to implement the CompareTo function because Droid implements IDroid, and IDroid implements IComparable
public int CompareTo(Object obj)
{
// If the obj that is passed in is null, just return 1. Unable to compare
if (obj == null)
{
return(1);
}
// Cast the obj to a droid.
Droid droid = (Droid)obj;
// Check to see if the droid is null. Perhaps the cast will fail and droid will be null.
if (droid != null)
{
// Do the comparison. Rather than doing the work of returning -1, 0, or 1
// I just delegated the work to the CompareTo method of decimal
return(this.TotalCost.CompareTo(droid.TotalCost));
}
// Else, the droid is null, so the droid that was passed in must not have been a droid.
// Throw an exception stating so.
else
{
throw new ArgumentException("Object is not a Droid");
}
}
// CompareTo Method
public int CompareTo(object obj)
{
if (obj == null)
{
return(1);
}
Droid otherDroid = obj as Droid;
if (otherDroid != null)
{
return(this.totalCost.CompareTo(otherDroid.totalCost));
}
else
{
throw new ArgumentException("Object is not a Droid");
}
}
// CompareTo method required by IComparable
public int CompareTo(object obj)
{
if (obj == null)
{
return(1);
}
// Get second element
Droid otherDroid = obj as Droid;
// Go on to compare if second element is not null
if (otherDroid != null)
{
// Calculate total cost for both elements and compare them
otherDroid.CalculateTotalCost();
this.CalculateTotalCost();
return(totalCost.CompareTo(otherDroid.totalCost));
}
else
{
throw new ArgumentException("Object is not a Droid");
}
}