标签：隐藏 virt 对象 font fresh 转换 highlight 面向 info
1.理解松耦合设计思想
2.掌握面向对象设计原则
3.掌握重构技法改善设计
4.掌握GOF核心设计模式
1.底层思维：向下，如何掌握机器底层，从微观理解对象构造
→封装，隐藏内部实现
→继承，复用现有代码
→多态，改写对象行为
2.抽象思维：向上，如何将周围世界抽象为程序代码
变化！！！！
。。。。
1.分解：人们面对复杂性有一个常见的做法：即分而治之，将大问题分解成多个小问题，将复杂问题分解为多个简单问题。（面向过程思想）
2.更高层次来讲，人们处理复杂性有一个共同技术，即抽象。由于不能掌握全部的复杂对象，我们选择忽略它的非本质，从而处理泛华和理想化了的对象模型。（现象对象思想）
面向过程实现：
Shape.h
class Point { public: int x; int y; }; class Line { public: Point start; Point end; Line(const Point& start, const Point& end) { this->start = start; this->end = end; } }; class Rect { public: Point LeftUp; int width; int height; Rect(const Point& letfUp, int width, int height){ this->LeftUp = letfUp; this->width = width; this->height = height; } };
MaintForm.cpp
class MainForm :publuc Form
{
privat:
Point p1;
Point p2;
vector<line> lineVector;
vevtor<Rect> rectVector;
public:
MainForm() {
//...
}
protected:
virtual void OnMouseDown(const MouseEventArg& e);
virtual void OnMouseUp(const MouseEventArg& e);
virtual void OnPaint(const MouseEventArg& e);
};
void MainForm::OnMouseDown(const MouseEventArg& e) {
p1.x = e.X;
p1.y = e.Y;
Form::OnMouseDown(e);
}
void MainForm::OnMouseUp(const MouseEventArg& e) {
p2.x = e.X;
p2.y = e.Y;
if (rdoLine.Checled)
{
Line line(p1, p2);
lineVector.push_back(line);
}
else if
{
int width = abs(p2.x - p1.x);
int height = abs(p2.y - p1.y);
Rect rect(p1, width, height);
}
//...
this->Refresh();
Form::OnMouseUp(e);
}
void MainForm::Onpaint(const PaintEventArg& e)
{
//针对直线
for (int i = 0; i < lineVector.size(); i++)
{
e.Graphice.DrawLine(Pens.Red,
LineVector[i].start.x,
LineVector[i].start.y,
LineVector[i].end.x,
LineVector[i].end.y);
}
//针对矩形
for (int i = 0; i < rectVector.size(); i++)
{
e.Graphice.DrawLine(Pens.Red,
rectVector[i].leftup;
rectVector[i].width,
rectVector[i].height);
}
//...
Form::OnPaint(e);
}
面向对象实现方式
Shape.h
class Shape {
public:
virtual void Draw(const Graphics& a) = 0;
virtual ~Shape(){ };
};
class Point {
public:
int x;
int y;
};
class Line :public Shape {
public:
Point start;
Point end;
Line(const Point& start, const Point& end) {
this->start = start;
this->end = end;
}
//实现自己的Draw,负责画自己
virtual void Draw(const Graphics& g) {
g.DrawLine(Pens.Red
start.x, start.y, end.x, end.y);
}
};
class Rect
{
public:
Point LeftUp;
int width;
int height;
Rect(const Point& letfUp, int width, int height) {
this->LeftUp = letfUp;
this->width = width;
this->height = height;
}
//实现自己的Draw,负责画自己
virtual void Draw(const Graphics& g) {
g.DrawLine(Pens.Red
leftUp, width,height);
}
};
MainForm.cpp
class MainForm :publuc Form
{
privat:
Point p1;
Point p2;
//针对所有形状
vector<Shape*> shapeVector;
public:
MainForm() {
//...
}
protected:
virtual void OnMouseDown(const MouseEventArg& e);
virtual void OnMouseUp(const MouseEventArg& e);
virtual void OnPaint(const MouseEventArg& e);
};
void MainForm::OnMouseDown(const MouseEventArg& e) {
p1.x = e.X;
p1.y = e.Y;
Form::OnMouseDown(e);
}
void MainForm::OnMouseUp(const MouseEventArg& e) {
p2.x = e.X;
p2.y = e.Y;
if (rdoLine.Checled)
{
shapeVector.push_back(new line(p1, p2));
}
else if
{
int width = abs(p2.x - p1.x);
int height = abs(p2.y - p1.y);
shapeVector.push_back(new rect(p1, width, height));
}
//...
this->Refresh();
Form::OnMouseUp(e);
}
void MainForm::Onpaint(const PaintEventArg& e)
{
//针对所有形状
for (int i = 0; i < shapeVector.size(); i++)
{
shapeVector[i]->Draw(e.Graphics); //多态调用各负其责
}
//...
Form::OnPaint(e);
}
当需求变化时：
比如需要加画圆的需求。面向对象和面向过程的修改方式自己脑补。。。。
复用！
标签：隐藏 virt 对象 font fresh 转换 highlight 面向 info
原文地址：https://www.cnblogs.com/malloc1free/p/11087290.html
