How do you use classes that are in seperate files !?

Question

Im new to C#. Something that is really easy in Java & C++ I can't seem to get it work in C#. When you make a class yourself in Java you create a file called for example File1.java when you compile this it gets compiled in to a file called File1.class Lets say I want to make an object of a class that is in File2.class In File1.class You will have to define: Import File2.class; // The only condition is that both classes have to be in the same directory. After that you can start making objects of the File2 class. What I've learned from C# is that it is NOT necessary for the class name to have the same name as the file name. In C++ you would just simply write: #include File1.h // The name of the header file... Right now I'm using ASP .NET with C#. In my example.aspx file I have: In my CodeBehind.cs file I have: using System; using myown; public class File1 : Page { //Here I want to make an object of the second class File2 that is in a seperate file ! I called the second file SecondFile.cs namespace myown; public class File2 { // Definitions of properties methods fields and events. } MY QUESTION IS: HOW DO I TELL THE CODEBEHIND.CS FILE THAT IT HAS TO LOOK IN SECONDFILE.CS TO FIND THE CLASS FILE2 This shouldn't be very hard !???? Anybody HELP !?

Mahesh Chand · Answer

It's not that hard. You're missing a namespace declaration in your files. If all .cs files belong to the same project add a namespace declaration in the beginning of the class. All files can belong to same or different namespaces. If its the same namespace class should be available every where in the project. But if a calling class belong to a different namespace than the caller class you use using namespace declaration on the top of the caller class.