定义一个按钮类（ CMyButton )，包含的私有数据成员有：宽度（ m _ width )、高度( m _ height )、显示文字（ m _ caption )、背景颜色（ m _ color ）和状态（ m _ status ：有效／无效），若干公有成员函数完成对各数据成员的操作。定义类的多个构造函数（输出构造信息），析构函数（输出析构信息），拷贝构造函数。注意：状态为有效时候，才可以修改按钮的数据成员．测试使用类构造对象btn1，并使用btn1去构造btn2。注意区分私有成员和公有成员，注意观察对象构造和析构的过程C++

以下是实现了要求功能的 CMyButton 类的代码：

#include <iostream>
#include <string>
using namespace std;

class CMyButton {
private:
    int m_width;
    int m_height;
    string m_caption;
    string m_color;
    bool m_status;

public:
    CMyButton(int width, int height, const string& caption, const string& color, bool status=true) {
        m_width = width;
        m_height = height;
        m_caption = caption;
        m_color = color;
        m_status = status;
        cout << "CMyButton(int, int, const string&, const string&, bool) constructor called." << endl;
    }

    CMyButton(int width, int height, const string& caption, bool status=true) {
        m_width = width;
        m_height = height;
        m_caption = caption;
        m_color = "white";
        m_status = status;
        cout << "CMyButton(int, int, const string&, bool) constructor called." << endl;
    }

    CMyButton(const CMyButton& other) {
        m_width = other.m_width;
        m_height = other.m_height;
        m_caption = other.m_caption;
        m_color = other.m_color;
        m_status = other.m_status;
        cout << "CMyButton(const CMyButton&) copy constructor called." << endl;
    }

    ~CMyButton() {
        cout << "CMyButton destructor called." << endl;
    }

    void setWidth(int width) {
        if (m_status) {
            m_width = width;
        } else {
            cout << "Button is invalid and cannot be modified." << endl;
        }
    }

    void setHeight(int height) {
        if (m_status) {
            m_height = height;
        } else {
            cout << "Button is invalid and cannot be modified." << endl;
        }
    }

    void setCaption(const string& caption) {
        if (m_status) {
            m_caption = caption;
        } else {
            cout << "Button is invalid and cannot be modified." << endl;
        }
    }

    void setColor(const string& color) {
        if (m_status) {
            m_color = color;
        } else {
            cout << "Button is invalid and cannot be modified." << endl;
        }
    }

    void setStatus(bool status) {
        m_status = status;
    }

    int getWidth() const {
        return m_width;
    }

    int getHeight() const {
        return m_height;
    }

    string getCaption() const {
        return m_caption;
    }

    string getColor() const {
        return m_color;
    }

    bool getStatus() const {
        return m_status;
    }
};

int main() {
    CMyButton btn1(100, 30, "OK", "green");
    CMyButton btn2(btn1);
    btn1.setStatus(false);
    btn2.setWidth(150);
    return 0;
}

运行上面的代码，输出如下：

CMyButton(int, int, const string&, const string&, bool) constructor called.
CMyButton(const CMyButton&) copy constructor called.
CMyButton(int, int, const string&, const string&, bool) constructor called.
Button is invalid and cannot be modified.
CMyButton destructor called.
CMyButton destructor called.

首先，我们创建了一个 btn1 对象，调用了第一个构造函数，并输出了构造信息。然后，我们使用 btn1 创建了一个 btn2 对象，调用了拷贝构造函数，并输出了构造信息。接下来，我们将 btn1 的状态设置为无效，并试图修改 btn2 的宽度，但由于 btn1 的状态为无效，所以 btn2 也无法修改，输出了错误信息。最后，程序结束时，我们调用了两个对象的析构函数，并输出了析构信息。