Design classes in C#

Question

Recently I had attended an interview and was given this question:

Question: With the following entities with you, design a class diagram or skeleton code:

The entities are:

garment shirt pant fabric buttons zip

The best I could do was this:


class Shirt : Fabric 
{
  Buttons buttons {get;set;}
  //Inherits all Fabric methods

  MakeShirt()  
  {
    //make a shirt here
  }
}

class Pant : Fabric
{
  Buttons buttons {get;set;}
  // Inherits all Fabric methods

  MakePant()
  {
     //Make a pant here
  }
}


class Fabric
{
  private MaterialType materialType {get;set;}
  private FabricType fabricType {get;set;}

  Fabric(MaterialType mType, FabricType fType)
  {
     this.materialType = mtype;
     this.fabricType = fType;
  }

  public GetFabricMaterial();
  public GetFabricType();

}

class Garment : IGarment
{
  Price price {get;set;}
  Audience audience {get;set;}
}

enum FabricType
{
  Fabric_Formal,
  Fabric_Casual,
}

enum MaterialType
{
   Fabric_Cotton,
   Fabric_Silk,
   Fabric_Wool, 
}

class Buttons
{
Color color {get;set;}
Shape shape {get;set;}
}

class Zip
{
Color color {get;set;}
Size size {get;set;}
}

But still I can see many things missing out from the above skeleton code.

1. How can I relate Garment with the other entities (Object relationship! ?)
2. What can be the return type of functions MakeShirt() and MakePant() ?
3. While answering these questions, what approach is best ? In other words, how to approach these type of questions ?

Any inputs on this is appreciated. (If this is not the right question to be asked here, kindly let me know to move this to the right stackoverflow site!)

Answer 1

I think you over thought this, I see it as this. Pants and Shirts are Garment. Garments are made up of Fabric.

Pants have Zip, shirts have buttons..

public enum Fabric { Cotton, Silk, Poly }

public abstract Garment{


    public Fabric Fabric {get; set; }
}

class Buttons
{
  Color color {get;set;}
  Shape shape {get;set;}
}
class Zip
{
   Color color {get;set;}
   Size size {get;set;}
}

public class Shirt : Garment{
   public Buttons Buttons { get; set;} 
}
public class Pants : Garment{
  public Zip Zip { get; set;}
}

Answer 2

This is more an exercise in parent/child relationships. I would have thought Garment is your abstract base class from which Shirt and Pant inherit. Fabric, Buttons and Zip are all properties of a Garment.

I wouldn't have specific Make methods. The constructor for the specific Garment types should make the Garment type ready to go instead of post initialising it.