Call a function From Class file without creating Object of that class

Question

I have created a function in a class. and i want to call it throughout my project. but i don't want to create the object of that class in every page. is there any global declaration for that class so that we can call in every page ? Inheritance is not possible in code behind file of aspx page .cs file.

Answer 1

You need to create a Static Method in your class so that you can call the function without creating an object of that class as shown in following snippet:

public class myclass
{
 public static returntype methodname()
 {
    //your code
 }
}

to call the function just use

//ClassName.MethodName();
myclass.methodname();

you can have look at MSDN: Static Members

Suggestion

One more resolution to your problem is to make use of SINGLETON DESIGN PATTERN

Intent

1. Ensure that only one instance of a class is created.
2. Provide a global point of access to the object.

Answer 2

You just need to make it a static method:

public class Foo
{
    public static void Bar()
    {
        ...
    }
}

Then from anywhere:

Foo.Bar();

Note that because you're not calling the method on an instance of the type, there won't be any instance-specific state - you'll have access to any static variables, but not any instance variables.

If you need instance-specific state, you'll need to have an instance - and the best way of getting hold of an appropriate instance will really depend on what you're trying to achieve. If you could give us more information about the class and the method, we may be able to help you more.

Admittedly from what I remember, dependency injection in ASP.NET (pre-MVC) is a bit of a pain, but you may well want to look into that - if the method mutates any static state, you'll end up with something which is hard to test and hard to reason about in terms of threading.