DataSet ds1 = new DataSet(), ds2 = new DataSet();
DataTable t1 = ds1.Tables.Add();			
DataTable t2 = ds2.Tables.Add();
for (int i = 1; i <= 2; i++) {
	t1.Columns.Add("C" + i.ToString(), typeof(int));
	t2.Columns.Add("C" + i.ToString(), typeof(int));				
}
for (int i = 0; i <= 5; i++) {
	t1.Rows.Add(new object[] { i, i});
}
for (int i = 0; i <= 100; i++) {
	t2.Rows.Add(new object[] { i, i });
}
for (int i = 0; i < 5; i++) {
	DataRow[] good = t2.Select("(C1 = '" + t1.Rows[i][0].ToString() + "') AND (C2 = '" + t1.Rows[i][1].ToString() + "')");
	if (good.Length > 0) { 
		// (...)
	}
}

Virtual functions

When you have a function defined in a class which you want to allow to be implemented by the inherited classes you can use virtual function.
The virtual function could be implemented by the inherited classes in their own way and the call to the method is decided at runtime.

New Modifier

The new modifier creates the New instance(object) of the class

Nitin Sawant wrote:

The new modifier creates the New instance(object) of the class

Malcolm Smart wrote:

and the compiler should hide one of the same name / signature in a base class

class A
{
	public void SomeMethod()
	{
		Console.WriteLine("Base called");
	}
}
class B : A
{
	public new void SomeMethod()
	{
		Console.WriteLine("New called");
	}
}
public static void Main()
{
	A instance = new B();
	if (instance is B)
		instance.SomeMethod();   // ??
	RL();
}

gajatko wrote:

Nb. if A.SomeMethod would be virtual and overriden in B, then "New called" would be displayed.

gajatko wrote:

public new void SomeMethod()

gajatko wrote:

A instance = new B();

Nitin Sawant wrote:

but i want that from codeproject.com

Nitin Sawant wrote:

i know there are many results on google but i want that from codeproject.com

Nitin Sawant wrote:

i'm new here

MarkBrock wrote:

Has anyone ever tryed, to make a program that could crack the ipod's lock for it's volume limiter (or perhaps heard of one)?