Generic Comparer Implementation

Question

Hi, I am trying to implement a generic comparer, as you can see (from the code below), this is probably the most raw / bad form of an implementation. I want it to work for all types, used if conditions for each data type, then realized that I am heading
in the wrong direction. There must be an efficient way of writing it.
I was trying to see if I can look at how Comparer<T> was implemented which derives from IComparer and IComparer<T>. But the code is not visible. Perhaps using reflection, might be possible. But I want to understand the idea behind a good comparer
solution. Any help is much appreciated
Thanks
public class MyGenericComparer<T>
public int Compare(T x, T y)
if (typeof(T) == typeof(String))
return ((string)(object)x).CompareTo((string)(object)y);
if (typeof(T) == typeof(int))
return ((int)(object)x).CompareTo((int)(object)y);
return -999;

Answer 1

In case you are asking what the good of an IComparer<T> is, this is the answer.
IComparer<T> is provided in order to let developers use any comparison algorithms they prefer when instances of their classes or types are about to being compared. For example in an array of Product type, the default comparison for Product instances
is compare based on reference, because they are object (reference-types).
But, many scenarios exist that you might not want your objects are compared based on their reference. Suppose you want to sort your array of products based on their Weight, Price, Title, StockDate or whatever rule you might want.
IComparer<T> is for such occasions. You can implement this interface in a class and give an instance of it to Array.Sort(). Then the array uses your custom comparer to sort your objects. 
class Product
public string Title;
public float Price;
public int Code;
public bool InStock;
public Product(string title, float price, int code, bool inStock)
Title = title;
Price = price;
Code = code;
InStock = inStock;
class ProductPriceComparer: System.Collections.IComparer, System.Collections.Generic.IComparer<Product>
// unchanged sections omitted
public int Compare(Product x, Product y)
if ((x == null) && (y == null))
return 0; // null is equal to null
if (x == null)
return -1; // null is lower than anything
if (y == null)
return 1; // anything is greater than null
int result;
if (x.Price > y.Price)
result = 1;
else if (x.Price < y.Price)
result = -1;
else
result = 0;
return result;
Product[] products = new Product[]
new Product("HTC Desire S", 590.0f, 10025, true),
new Product("Sony Ericsson Xperia Neo", 590.0f, 10032, true),
new Product("Nokia X7", 570.0f, 10021, true),
new Product("Motorola Atrix", 830.0f, 10034, false),
new Product("LG Optimus One P500", 270.0f, 10035, true),
new Product("Samsung I9100 Galaxy", 800.0f, 10029, true),
new Product("Apple iPhone 4", 900.0f, 10024, false),
new Product("Asus Eee Pad Transformer TF101", 750.0f, 10028, true),
new Product("Archos 101 Internet Tablet", 450.0f, 10030, true)
Product p;
Console.WriteLine("\nSort by price…");
Array.Sort(products, new ProductPriceComparer());
for (int i = 0; i < products.Length; i++)
p = products[i];
Console.WriteLine("{0}: {1} ({2}$)", i + 1, p.Title, p.Price);
You can implement as many comparer as you want.