临时变量管理器
问题
有些变量,它们在特定的情况下才有意义。有些功能需要多步才能完成,结果就需要一些中间变量保存过程的状态,过程结束后变量就失去存在的价值。缺点:
- 浪费存储空间,虽然内存很廉价,但还是能省则省
- 中间变量变多的时候,所在类越来越大,越来越难以理解
解决方案
封装一个中间变量管理器:支持创建、删除、取值、设值这几个操作就行。
临时变量定义:
class Player { public: enum TempVariableType { kTempInvalid, kTempTest, kTempJumpVerification, }; TempVariableManager<Player> tmpvars; }; struct JumpVerification { JumpVerification(DWORD x_=0, DWORD y_=0, DWORD mapid_=0) : x(x_), y(y_), mapid(mapid_) {} DWORD x; DWORD y; DWORD mapid; }; // 中间变量的定义 define_tempvariable(Player, kTempTest, DWORD); define_tempvariable(Player, kTempJumpVerification, JumpVerification);
临时变量的使用:
// 新创建 pUser->tmpvars.create<SceneUser::kTempTest>(20); pUser->tmpvars.create<SceneUser::kTempJumpVerification>(JumpVerification(10,10,101)); // 删除 pUser->tmpvars.release(SceneUser::kTempTest); pUser->tmpvars.release(SceneUser::kTempJumpVerification); // 取值 pUser->tmpvars.get<SceneUser::kTempTest>(); pUser->tmpvars.get<SceneUser::kTempJumpVerification>().x pUser->tmpvars.get<SceneUser::kTempJumpVerification>().y JumpVerification& jv = pUser->tmpvars.get<SceneUser::kTempJumpVerification>(); jv.x; jv.y; // 设值 pUser->tmpvars.get<SceneUser::kTempTest>() = 100; pUser->tmpvars.get<SceneUser::kTempJumpVerification>().x = 100; JumpVerification& jv = pUser->tmpvars.get<SceneUser::kTempJumpVerification>(); jv.x = 100; jv.y = 100;
2012/05/08 21:00 于上海