testing posting 10 on 10

Feedbook demo is going on …

This new rich text testing

• This is test text

Post has been moved too another blog >> http://csharplive.wordpress.com/2008/09/11/wpf-data-binding-observablecollection-cross-thread-binding-support/

Manifest-Version: 1.0 <CR><F>
Main-Class: ssm.Main <CR><F>
Class-Path: lib\avanza.core.jar lib\comm.jar

Then solutions is very simple just hit enter at end of Class-Path line and save it. It will put carriage return and line feed, which seem to be required by JVM

Class-Path: lib\avanza.core.jar lib\comm.jar <CR><F>

namespace VirtualWorkAround
{
    abstract class BaseClass<T> where T : BaseClass<T>, new()
    {
        private static T obj = new T();

        public abstract string ImplementAsStatic();

        public static string CallStaticImplementation()
        {
            return obj.ImplementAsStatic();
        }

    }

    class DriveClassA : BaseClass<DriveClassA>
    {
        private static int instanceCount = 0;

        public DriveClassA()
        {
            instanceCount++;
        }

        public override string ImplementAsStatic()
        {
            return "I am drive class A, instance count: " + instanceCount;
        }
    }

    class DriveClassB : BaseClass<DriveClassB>
    {
        private static int instanceCount = 0;

        public DriveClassB()
        {
            instanceCount++;
        }

        public override string ImplementAsStatic()
        {
            return "I am drive class B, instance count: " + instanceCount;
        }
    }

    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine(BaseClass<DriveClassA>.CallStaticImplementation());
            // output: I am drive class A, instance count: 1 

            Console.WriteLine(BaseClass<DriveClassB>.CallStaticImplementation());
            // output: I am drive class B, instance count: 1

            Console.WriteLine(BaseClass<DriveClassA>.CallStaticImplementation());
            // output: I am drive class A, instance count: 1 Console.ReadKey();
        }
    }
}

Linq stands for Language integrated query, which simply means that languages like C# and VB starts supporting quering on objects. DLinq (now called Linq to SQL ) and XLinq are part of Linq project. When Linq project announce by microsoft they market this new feature as declerative programming (or goal oriented programming). Declerative programming mean you tell the system what results you want by giving criteria rather then fetching result and then filtering out yourself. Programming language which we are working called Primitive or 3G Languages.

Now we know that Linq is declarative programming, so is it new language? have we did some programming in it? Answer to first question is no, and second question is off course yes. SQL is always been declarative language and sure do we all program in it. Linq is modified version of SQL language. It is twisted little bit to fit compiler needs. Lets look at an example; Consider we have Customer object and it contains Name, City, Age and etc. Now if we want customer names that belong to Karachi, in typical way is:

(Note: due to html content hosting some of special characters will not be displayed)

public class Customer
{
    public string Name { get; set; }
    public string City { get; set; }
    public byte Age { get; set; }
}

List<string> karachiCustomerNames = new List<string>();

foreach (Customer customer in customerList)
    if (customer.City == "Karachi")
        karachiCustomerNames.Add(customer.Name);

Now if we do that in Linq:

IEnumerable<string> karachiCustomerNames = from customer in customerList

                                           where customer.City == "Karachi"

                                           select customer.Name;

Ha! what is that? It is SQL only the “select” clause comes last rather then before. It is twisted in a way just to support Intellisense and compiler to actually now what customer object is in select clause. This feature can be obtain in VS 2005 by installing LINQ Preview May 2006 CTP . Standard query operators aspects

Here I give and idea about Linq but there is much more in Linq and new C# 3.0. do try out