How the default value initialized even not specified in explicit constructor in c#

Question

Declared variable and not initialized in explicit constructor. Then how the default value initialized to the variable.is it initialization done by the implicit constructor?

Ex:

class A
{
    int i;
    public A()
    {
    }  
}

class program
{
    static void Main(string[] args)
    {
        A a = new A();
        Console.Write(a.i);
    }
}

Output: 0

Answer 1

If you don't initialize a member variable then it gets assigned the value default(T) where T is the type.

For reference types this is null . For bool it is false and for other value types it is whatever the state of the object would be it the memory for it was zeron-initialized. Thus for int it it 0 .

Answer 2

int is a value type and cannot be null unless you declare it as a nullable int (int?). It's default value is 0.

Answer 3

you have taken i as int , and Integer is value type with a default value is 0

Check below link, if you're new in C#

Default Value

Value Type

Reference Type

Use ? , If you don't want to assign a default value. see below example