Inner class and Outer class in c#

Question

how to implement inner outer classes in c#

i have two nested classes

like

class Outer
{
    int TestVariable = 0;
    class Inner
    {
              


        

Answer 1

You can create an instance of inner class without even have outer class instance, what should happen in that case you think? That's why you can't use it

Outer.Inner iner = new Outer.Inner(); // what will be InnerTestVariable value in this case? There is no instance of Outer class, and TestVariable can exist only in instance of Outer

Here is one of the ways to do it

  class Outer
    {
        internal int TestVariable=0;
        internal class Inner
        {
            public Inner(int testVariable)
            {
                InnerTestVariable = testVariable;
            }
           int InnerTestVariable; //Need to access the variabe "TestVariable" here
        }
        internal Inner CreateInner()
        {
            return new Inner(TestVariable);
        }
    }