boost::function 用来注册函数(switch N多case的解决方案)
[cpp]
<SPAN style="FONT-FAMILY: Arial, Helvetica, sans-serif">在现在做的游戏开发的项目中，需要根据道具类型调用不同的接口，通常的写法是用</SPAN>
在现在做的游戏开发的项目中，需要根据道具类型调用不同的接口，通常的写法是用[cpp] view plaincopyprint?
switch(itemType)
{
case ...;
case ...;
.
.
.
}
switch(itemType)
{
case ...;
case ...;
.
.
.
}这样写的话，如果将来有新增情况会导致case越来越多 ，不好。
正好项目中使用了boost库，结果老大给了个解决方案：
[cpp]
typedef boost::function<void(long long, int)> TypeOnUseItemHandler; // 回调函数返回void 参数一个是long long型，一个是int型
map<int, TypeOnUseItemHandler> _handlers; // 定义map<key, value> key是case的条件 value是执行的接口
typedef boost::function<void(long long, int)> TypeOnUseItemHandler; // 回调函数返回void 参数一个是long long型，一个是int型
map<int, TypeOnUseItemHandler> _handlers; // 定义map<key, value> key是case的条件 value是执行的接口[cpp] view plaincopyprint?
<SPAN style="WHITE-SPACE: pre"> </SPAN>// 注册
_handlers[ItemSpecialAttrId::TimeOfDuration] = boost::bind(&ItemManager::UseTimeOfDuration, this, _1, _2);
_handlers[ItemSpecialAttrId::StorgeHpVolume] = boost::bind(&ItemManager::UseStorgeHpVolume, this, _1, _2);
_handlers[ItemSpecialAttrId::IsGetItem] = boost::bind(&ItemManager::UseIsGetItem, this, _1, _2);
_handlers[ItemSpecialAttrId::ItemBuff] = boost::bind(&ItemManager::UseItemBuff, this, _1, _2);
_handlers[ItemSpecialAttrId::Bind] = boost::bind(&ItemManager::UseBind, this, _1, _2);
_handlers[ItemSpecialAttrId::ReinforceLevel] = boost::bind(&ItemManager::UseReinforceLevel, this, _1, _2);
_handlers[ItemSpecialAttrId::AddPartnerExp] = boost::bind(&ItemManager::UseAddPartnerExp, this, _1, _2);
_handlers[ItemSpecialAttrId::AddRoleExp] = boost::bind(&ItemManager::UseAddRoleExp, this, _1, _2);
_handlers[ItemSpecialAttrId::AddSliver] = boost::bind(&ItemManager::UseAddSliver, this, _1, _2);
_handlers[ItemSpecialAttrId::AddGold] = boost::bind(&ItemManager::UseAddGold, this, _1, _2);
_handlers[ItemSpecialAttrId::AddGoldNote] = boost::bind(&ItemManager::UseAddGoldNote, this, _1, _2);
_handlers[ItemSpecialAttrId::SynthMaterial] = boost::bind(&ItemManager::UseSynthMaterial, this, _1, _2);
_handlers[ItemSpecialAttrId::EnhanceNpcExp] = boost::bind(&ItemManager::UseEnhanceNpcExp, this, _1, _2);
_handlers[ItemSpecialAttrId::GetAttribute] = boost::bind(&ItemManager::UseGetAttribute, this, _1, _2);
_handlers[ItemSpecialAttrId::GainReinforceProp] = boost::bind(&ItemManager::UseGainReinforceProp, this, _1, _2);
// 注册
_handlers[ItemSpecialAttrId::TimeOfDuration] = boost::bind(&ItemManager::UseTimeOfDuration, this, _1, _2);
_handlers[ItemSpecialAttrId::StorgeHpVolume] = boost::bind(&ItemManager::UseStorgeHpVolume, this, _1, _2);
_handlers[ItemSpecialAttrId::IsGetItem] = boost::bind(&ItemManager::UseIsGetItem, this, _1, _2);
_handlers[ItemSpecialAttrId::ItemBuff] = boost::bind(&ItemManager::UseItemBuff, this, _1, _2);
_handlers[ItemSpecialAttrId::Bind] = boost::bind(&ItemManager::UseBind, this, _1, _2);
_handlers[ItemSpecialAttrId::ReinforceLevel] = boost::bind(&ItemManager::UseReinforceLevel, this, _1, _2);
_handlers[ItemSpecialAttrId::AddPartnerExp] = boost::bind(&ItemManager::UseAddPartnerExp, this, _1, _2);
_handlers[ItemSpecialAttrId::AddRoleExp] = boost::bind(&ItemManager::UseAddRoleExp, this, _1, _2);
_handlers[ItemSpecialAttrId::AddSliver] = boost::bind(&ItemManager::UseAddSliver, this, _1, _2);
_handlers[ItemSpecialAttrId::AddGold] = boost::bind(&ItemManager::UseAddGold, this, _1, _2);
_handlers[ItemSpecialAttrId::AddGoldNote] = boost::bind(&ItemManager::UseAddGoldNote, this, _1, _2);
_handlers[ItemSpecialAttrId::SynthMaterial] = boost::bind(&ItemManager::UseSynthMaterial, this, _1, _2);
_handlers[ItemSpecialAttrId::EnhanceNpcExp] = boost::bind(&ItemManager::UseEnhanceNpcExp, this, _1, _2);
_handlers[ItemSpecialAttrId::GetAttribute] = boost::bind(&ItemManager::UseGetAttribute, this, _1, _2);
_handlers[ItemSpecialAttrId::GainReinforceProp] = boost::bind(&ItemManager::UseGainReinforceProp, this, _1, _2);
[cpp]
<SPAN style="WHITE-SPACE: pre"> </SPAN>//<SPAN style="FONT-FAMILY: Arial, Helvetica, sans-serif">specialAttrId 是外部传递过来的参数 对应map中的key</SPAN>
map<int, TypeOnUseItemHandler>::iterator itFind = _handlers.find(specialAttrId);
if (itFind == _handlers.end())
return;
if (itFind->second)
itFind->second(roleId, specialAttrValue);
//specialAttrId 是外部传递过来的参数 对应map中的key
map<int, TypeOnUseItemHandler>::iterator itFind = _handlers.find(specialAttrId);
if (itFind == _handlers.end())
return;
if (itFind->second)
itFind->second(roleId, specialAttrValue);
这样写 通过注册的方式来调用不同的函数接口，看着舒服多了，也灵活多了， 到有新增的case情况 直接填写一个：
[cpp]
_handlers[ItemSpecialAttrId::GainReinforceProp] = boost::bind(&ItemManager::UseGainReinforceProp, this, _1, _2);
补充：软件开发 , C++ ,
