c++设计模式-行为型模式-状态模式

#include "context.h" #include "concretestatea.h" Context::Context() { //定义环境类的初始状态 mState = new ConcreteStateA(); } Context::~Context() { // 释放最后的状态 if (mState) { delete mState; } } void Context::setState(IState *state) { // 设置新的状态前先示范已有状态 if (mState) { delete mState; mState = nullptr; } mState = state; } IState *Context::getState() { return mState; } void Context::Handle() { if (mState) { mState->Handle(this); } }