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Overload Operator ==

AIt is derived directly from the class Object, instead of Aor Objectoverload ==, so why the following code does not cause an error:

class Program
{
    static void Main(string[] args)
    {
        A a1 = new A();
        A a2 = new A();

        if (a1 == a2) ... ;
    }
}

class A { }

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6 answers

A comes directly from the Object class and is not an A or Object overload == operator, so why doesn't the following code throw an error?

As in the case of your other question, you seem to have a strange belief that there is any overloaded operator, does it have any relation to whether it is possible to choose the operator meaningfully. This is not .

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== ( ) a1 a2. A, a1 == a2 false .

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==, , ( ). . .

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Object , .

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The basic operator ==is invoked so that it does not give any errors.

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By default, the == operator checks reference equality by determining if two links point to the same object, so reference types are not needed to implement the == operator to get this functionality.

From: http://msdn.microsoft.com/en-us/library/ms173147(v=vs.80).aspx

An important bit regarding your question:

reference types do not need to execute the == operator to get this functionality

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