Accessing classes

I have a problem in C# that I have faced a few times before, but I have always managed to work around it. Basically, I need to, from one class, access another class that has not been created in the current class. Both classes are in the same namespace.

Example:

Code:

//Form1.cs
ClassTwo testClass;

public void Initialize()
{
	testClass = new ClassTwo();
	testClass.doTest();
}

public void aTest(string text)
{
	this.Text=text;
}
//End of Form1.cs


//ClassTwo.cs

public void doTest()
{
	Form1.aTest("This is a test");
}

//End of ClassTwo.cs

This is basically what I want to do. But it won't allow me to access the method(s) in Form1. How can I do this without creating a second instance of Form1?

You can create a static method in Form1. Info on static classes and members.

You can pass the class to the other class :

Code:

public class SomeClass() { 
public const test = "Hello world!";
}

public void doTest(SomeClass SC){
try{
Console.Write( SC.test );
}
catch(Exception e){
Console.Write( e.ToString() ); // SC is null or something.
}
}