Note 1: a little bit

1. face important features of Objects

Encapsulation

Inheritance

Polymorphism

2. constructor and sufficient analysis functions

■ Constructor and destructor are implicitly called by the program and cannot be displayed by the user.

■ Neither the constructor nor the Destructor returns a value.

■ Constructor and destructor cannot be inherited

■ Destructor can be virtual and constructor cannot

■ It is best not to do anything other than assigning an initial value to the constructor.

3. default parameter problems

In C ++, you can define the default value for the parameter:

Class person

{

... ...

PRIVATE:

Float m_weight;

... ...

Void setweight (float Weight = 50 );

};

Void person: setweight (float weight)

{

M_weight = weight;

}

Call the following code:

Person you;

You. setweight ();

M_weight is set to 50 by default.

　　

Note:

■ The default parameter value can only be given in the function prototype, and cannot be given again in the function definition.

■ A function may have many default parameters, but it must be placed continuously at the end of the function.

Error:

Void myfunc (int A = 1, B, c = 2 );

Void myfunc (int A = 1, C = 2, B );

Correct:

Void myfunc (int B, A = 1, C = 2 );