What's a “static method” in C#?

Question

What does it mean when you add the static keyword to a method?

public static void doSomething(){
   //Well, do something!
}

Can you add the static keyword to class? What would it mean then?

Answer 1

Static variable doesn't link with object of the class. It can be accessed using classname. All object of the class will share static variable.

By making function as static, It will restrict the access of that function within that file.

Answer 2

A static method, field, property, or event is callable on a class even when no instance of the class has been created. If any instances of the class are created, they cannot be used to access the static member. Only one copy of static fields and events exists, and static methods and properties can only access static fields and static events. Static members are often used to represent data or calculations that do not change in response to object state; for instance, a math library might contain static methods for calculating sine and cosine. Static class members are declared using the static keyword before the return type of the membe

Answer 3

Shortly you can not instantiate the static class: Ex:

static class myStaticClass
{
    public static void someFunction()
    { /* */ }
}

You can not make like this:

myStaticClass msc = new myStaticClass();  // it will cause an error

You can make only:

myStaticClass.someFunction();

Answer 4

A static function, unlike a regular (instance) function, is not associated with an instance of the class.

A static class is a class which can only contain static members, and therefore cannot be instantiated.

For example:

class SomeClass {
    public int InstanceMethod() { return 1; }
    public static int StaticMethod() { return 42; }
}

In order to call InstanceMethod, you need an instance of the class:

SomeClass instance = new SomeClass();
instance.InstanceMethod();   //Fine
instance.StaticMethod();     //Won't compile

SomeClass.InstanceMethod();  //Won't compile
SomeClass.StaticMethod();    //Fine

Answer 5

The static keyword, when applied to a class, tells the compiler to create a single instance of that class. It is not then possible to 'new' one or more instance of the class. All methods in a static class must themselves be declared static.

It is possible, And often desirable, to have static methods of a non-static class. For example a factory method when creates an instance of another class is often declared static as this means that a particular instance of the class containing the factor method is not required.

For a good explanation of how, when and where see MSDN

Answer 6

When you add a "static" keyword to a method, it means that underlying implementation gives the same result for any instance of the class. Needless to say, result varies with change in the value of parameters