1.类与对象小案例（封装按钮）

#include <graphics.h>
#include <iostream>
#include <string>

using namespace std;

class Button {
public:
    Button() = default;
    Button(int x, int y, int width, int height, COLORREF inColor, COLORREF outColor, string text, COLORREF textColor) :
        x(x), y(y), width(width), height(height), inColor(inColor), outColor(outColor), 
        text(text), textColor(textColor),curColor(outColor) {}//构造时可以乱序

    void draw()
    {
        setfillcolor(curColor);
        fillrectangle(x, y, x + width, y + height);

        setbkmode(TRANSPARENT);
        settextstyle(25, 0, "楷体");
        settextcolor(textColor);
        int tW = textwidth(text.c_str());
        int tH = textheight(text.data());
        int tX = x + (width - tW) / 2;
        int tY = y + (height - tH) / 2;
        outtextxy(tX, tY, text.data());

    }
    bool mouseInButton(MOUSEMSG msg)
    {
        if (msg.x > x && msg.x<x + width && msg.y>y && msg.y < y + height) {
            curColor = inColor;
            return true;
        }
        curColor = outColor;
        return false;
    }
protected:
    int x;
    int y;
    int width;
    int height;
    COLORREF inColor;
    COLORREF outColor;
    COLORREF curColor;
    string text;
    COLORREF textColor;
};

int main()
{
    initgraph(800, 600);
    Button b = { 100,100,150,50,GREEN,WHITE,"BUTTON",BLACK };
    Button c(400, 100, 150, 50, GREEN, WHITE, "BUTTON_O", BLACK);
    MOUSEMSG msg;
    BeginBatchDraw();
    while (1) 
    {
        b.draw();
        c.draw();
        msg = GetMouseMsg();
        if (b.mouseInButton(msg)&&msg.uMsg==WM_LBUTTONDOWN) {
            break;
        }
        if (c.mouseInButton(msg) && msg.uMsg == WM_LBUTTONDOWN) {
            break;
        }
        FlushBatchDraw();
    }
    EndBatchDraw();
    closegraph();
    return 0;
}

2.图形库的输入

class Button {
public:
    Button() = default;
    Button(int x, int y, int width, int height, COLORREF inColor, COLORREF outColor, string text, COLORREF textColor) :
        x(x), y(y), width(width), height(height), inColor(inColor), outColor(outColor),
        text(text), textColor(textColor), curColor(outColor) {}//构造时可以乱序

    void draw()
    {
        setfillcolor(curColor);
        fillrectangle(x, y, x + width, y + height);

        setbkmode(TRANSPARENT);
        settextstyle(25, 0, "楷体");
        settextcolor(textColor);
        int tW = textwidth(text.c_str());
        int tH = textheight(text.data());
        int tX = x + (width - tW) / 2;
        int tY = y + (height - tH) / 2;
        outtextxy(tX, tY, text.data());

    }
    bool mouseInButton(MOUSEMSG msg)
    {
        if (msg.x > x && msg.x<x + width && msg.y>y && msg.y < y + height) {
            curColor = inColor;
            return true;
        }
        curColor = outColor;
        return false;
    }
protected:
    int x;
    int y;
    int width;
    int height;
    COLORREF inColor;
    COLORREF outColor;
    COLORREF curColor;
    string text;
    COLORREF textColor;
};

int main()
{
    initgraph(800, 600);
    Button b = { 100,100,150,50,GREEN,WHITE,"INPUT",BLACK };
    char name[20] = "";
    MOUSEMSG msg;
    BeginBatchDraw();
    while (1)
    {
        b.draw();
        msg = GetMouseMsg();
        if (b.mouseInButton(msg) && msg.uMsg == WM_LBUTTONDOWN) {
            InputBox(name, 20);//添加的代码，增加输入框
            settextcolor(WHITE);
            outtextxy(0, 0, name);
        }
        FlushBatchDraw();
    }
    EndBatchDraw();
    closegraph();
    return 0;
}