命令模式——示例——实现

//依 CSDN刘伟技术博客，C++命令模式示例如下：

 1 // Client.cpp

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

#include <FBSettingWindow.h>
#include <FunctionButton.h>
#include <Command.h>

int main(void)
{
//面板
    FBSettingWindow* fbsw = new FBSettingWindow("function key set panel");

//键号
    FunctionButton* fb1 = new FunctionButton("KEY 1");
    FunctionButton* fb2 = new FunctionButton("KEY 2");

//功能
    Command* command1 = new HelpCommand;
    Command* command2 = new MinimizeCommand;

//键号--功能
    fb1->setCommand(command1);
    fb2->setCommand(command2);

//面把上添加功能键
    fbsw->addFunctionButton(fb1);
    fbsw->addFunctionButton(fb2);

//调用功能键的业务方法
    fb1->onClick();
    fb2->onClick();

    delete command2;
    delete command1;
    delete fb2;
    delete fb1;
    delete fbsw;
    return 0;
}

// Command.cpp

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

#include <Command.h>
using namespace std;

MinimizeCommand::MinimizeCommand(void): whObj(NULL)
{
    whObj = new WindowHandler;
}

MinimizeCommand::~MinimizeCommand(void)
{
    if(whObj)
        delete whObj;
}

//命令执行方法：将调用请求接收者的业务方法
void MinimizeCommand::execute(void)
{
    whObj->minimize();
}

HelpCommand::HelpCommand(void): hhObj(NULL)
{
    hhObj = new HelpHandler;
}

//命令执行方法：将调用请求接收者的业务方法
void HelpCommand::execute(void)
{
    hhObj->display();
}

HelpCommand::~HelpCommand(void)
{
    if(hhObj)
        delete hhObj;
}                

// FBSettingWindow.cpp

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

#include <FBSettingWindow.h>
using namespace std;
//功能设置窗口类
FBSettingWindow::FBSettingWindow(void):title(NULL), functionButtons({NULL}) {}
                                                                                                                   
FBSettingWindow::~FBSettingWindow(void)
{
    if(title)
        delete[]title;
}

FBSettingWindow::FBSettingWindow(const char* str): title(NULL), functionButtons({NULL})
{
    title = new char[strlen(str) + 1];
    strcpy(title, str);
}

void FBSettingWindow::setTitle(const char *str)
{
    if(str != NULL)
        delete[] str;
    title = new char[strlen(str) + 1];
    strcpy(title, str);
}

const char* FBSettingWindow::getTitle(void)const
{
    return title;
}

void FBSettingWindow::addFunctionButton(FunctionButton* fb)
{
    int size = sizeof(functionButtons) / sizeof(functionButtons[0]);
    int i = 0;
    while(i < size) 
    {
        if(functionButtons[i] == NULL)
            break;
        i++;
    }

    if(i < size)
        functionButtons[i] = fb;
}

void FBSettingWindow::removeFunctionButton(FunctionButton* fb)
{
    int size = sizeof(functionButtons) / sizeof(functionButtons[0]);
    int i = 0;
    while(i < size)
    {
        if(functionButtons[i] == fb)
            break;
        i++;
    }

    if(i < size)
        functionButtons[i] = NULL;

}

//显示窗口及功能键
void FBSettingWindow::display(void)
{
    cout << "show window " << title << endl;
    cout << "show function keys" << endl;
    int size = sizeof(functionButtons) / sizeof(functionButtons[0]);
    int i = 0;
    while(i < size)
    {
        if(functionButtons[i] != NULL)
        {
            cout << functionButtons[i]->getName() << endl;
        }
        i++;
    }
}

// FunctionButton.cpp

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

using namespace std;
//功能键类：请求发送者
FunctionButton::FunctionButton(const char* str):name(NULL), command(NULL)
{
    name = new char[strlen(str) + 1];
    strcpy(name, str);
}
                                                                                                                   
FunctionButton::~FunctionButton(void)
{
    if(name)
        delete[]name;
}

const char* FunctionButton::getName(void)const
{
    return name;
}

//为功能键注入命令
void FunctionButton::setCommand(Command* cmd)
{
    command = cmd;
}
    
//发送请求的方法
void FunctionButton::onClick(void)
{
    cout << "click function key" << endl;
    command->execute();
}

// HelpHandler.cpp

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

using namespace std;
//帮助文档处理类:请求接收者
void HelpHandler::display(void)
{
    cout << "show help document" << endl;
}

// WindowHandler.cpp

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

#include <WindowHandler.h>
using namespace std;

//窗口处理类:请求接收者
void WindowHandler::minimize(void)
{
    cout << "minimize window size" << endl;
}