c# - Is the Main Function of a Class Called When an Object of That Class is Created?

Question

Closed. This question needs details or clarity. It is not currently accepting answers. question from:https://stackoverflow.com/questions/65862696/is-the-main-function-of-a-class-called-when-an-object-of-that-class-is-created

Answer 1

No. The code that runs automatically when you create a class is in the constructor, which is a method that has a name the same as the class (and no return type)

public class MyClass{
  public MyClass(){
    //this is the constructor. Code here is run automatically when you make a new MyClass
  }
}

Applications typically have a Main() somewhere, and it is called automatically when the app starts, but that is the only time it is called automatically and only one of the classes in the program has a main that is called automatically.

In other words, you can have as many classes (each with Main methods) as you like but you'll have to call them manually from your code if you want them to run

class Program{
  static void Main(string[] args){
    //this method will be called automatically to kick start your code running if..
    //it is configured in the project properties that Program shall be the startup object
  }
}
class MyClass{
  static void Main(string[] args){
    //this is also a method called main, but this one won't be called automatically, ever, 
    //if the project's Startup Object is set to Program
  }
}

If you have multiple classes with a Main you can choose which one will be called upon startup, in the project settings:

But from there on after if you have another class with a Main you have to call it yourself