public vs public static Methods

Question

Having read the access modifiers in C# progamming tutorial, I come to conclusion that defining a method public is enough for it to be "seen" from another Form of the same namespace.

However, in practise whenever I tried to implement this, I also had to define the method as static in order for it to be referenced from other Forms of the same namespace.

Am I loosing something? I am doing somethning wrong?

Did you create an instance of the class that the method resides in? Was the class marked as static too? Post some code — DGibbs, Mar 17 '13 at 18:28
Possible duplicate of [When should I use public/private/static methods?](http://stackoverflow.com/questions/793494/when-should-i-use-public-private-static-methods) — Ashraf Sada, Jul 31 '16 at 14:37

bas · Accepted Answer · 2013-03-17T18:57:43.367

7

For a public static method, you don't need a reference to an object. The method is static and can be accessed on class level.

If you can't access a public method, then you need a reference to the object, then you can.

public class AClass
{
    public void DoSomething() {}
    public static void DoSomethingElse() {}
}

You can use them as follows:

AClass.DoSomethingElse(); // no object reference required
AClass.DoSomething(); // will give compiler error, since you have no object reference.
var anObject = new AClass();
anObject.DoSomething(); // will work fine.
anObject.DoSomethingElse(); // compile error (thx hvd).

edited Mar 17 '13 at 18:57

answered Mar 17 '13 at 18:28

bas

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"anObject.DoSomethingElse(); // will also work fine" -- Are you sure? Mono's compiler gives a hard error "error CS0176: Static member cannot be accessed with an instance reference, qualify it with a type name instead", and I seem to recall seeing an error for that with Microsoft's compiler as well. – Mar 17 '13 at 18:37
In fact, that error code CS0176 [is Microsoft's code for that exact error](http://msdn.microsoft.com/en-us/library/zhcxt2bd%28v=vs.90%29.aspx). – Mar 17 '13 at 18:39

score 1 · Answer 2 · answered Mar 17 '13 at 18:35

public static method do not need object instance, they can be used without creating any instance of the class

ClassName.MyStaticPublicMethodName()

where as public (non-static) method require an Instance of the Class, public (non-static) method in general helps you to work with the data member (field) of the object.

To use a non-static public method you need to create instance of the class

ClassName obj = new ClassName();
obj.MyPublicMethod();

public vs public static Methods

2 Answers2