luaplus 与官方文档慢慢扯(三)

以下未知  占位

 

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Class: LuaStateAuto/Owner (Unmanaged Only)

LuaStateAuto is an auto pointer encapsulation for a LuaState pointer.  When the LuaStateAuto goes out of scope, LuaState::Destroy() is automatically called on the contained state.  In a Release build, LuaStateAuto's accessors are inlined, and code generation is as if the LuaStateAuto object did not even exist.

Using LuaStateAuto is illustrated below:

{    LuaStateAuto stateOwner;  // The state is automatically set to NULL.    stateOwner = LuaState::Create();    stateOwner->PushNil();    // LuaState::Destroy() is automatically called here.}

LuaStateOwner is derived from LuaStateAuto.  LuaStateOwner can automatically create the LuaState through the function call LuaState::Create.

{    LuaStateOwner stateOwner;  // Automatically calls LuaState::Create().    stateOwner->PushNil();    // LuaState::Destroy() is automatically called here.}

Since a LuaStateAuto object merely encapsulates the LuaState pointer, it is possible to retrieve that pointer by just assigning it.

LuaState* state = stateOwner;

a

Class: LuaObject
LuaObject封装了所有lua堆栈操作 甚至让你感觉到没有在操作lua堆栈
而且它比lua capi操作堆栈效率更高
LuaObject 还有一些特殊能力  这里我就不扯了  我自己也搞不太清楚
有兴趣的自己看
LuaPlus provides an API extension over the core of Lua wrapped in the class LuaObject.  A LuaObject gives the full functionality of core Lua's stack entities, but it does so without involving the stack at all.  In general, LuaObjects tend to run a little faster than the core Lua stack equivalent.
A LuaObject should be used for all communication with LuaPlus that is external to a callback function.  LuaStackObjects, described below, are used in conjunction with callback functions, but the same functional interface is provided for consistency.
LuaObjects store a pointer to the parent LuaState.  In part, this is what makes the LuaWatchAddin work.  Most importantly, LuaObjects can just be passed around without any regard for the LuaState they came from.
It is also important to note LuaObjects are scope-driven.  So long as the LuaObject is in scope, the object is valid.  When it goes out of scope, the contents of the LuaObject will be garbage collected.  There is no need to run commands like lua_ref() to keep an object around.  Merely holding onto the LuaObject instance, be it as a member variable, global variable, or even local variable within a block of code is enough to ensure the LuaObject's existence.
A Reset() function is also provided.  It resets the LuaObject back to a default state where no Lua state is pointed to internally.
The sample code TestSuite performs an in-depth test of LuaObject and is a useful supplement to this documentation.  The sample TestScript is also used as a test bed for LuaObject concepts.
Object Type
LuaObject可以包含任意一种lua定义的类型  还有一种 wide string type 这是LuaPlus自己定义的类型

有以下几种方法检测指定类型(当然 如果是数字 用 IsString返回的会是1 因为number可以转换成string 这是lua的特性不可避免的)
IsNil() - Tests if the object is nil.  Mirrors lua_isnil(). 
IsTable() - Tests if the object is a table.  Mirrors lua_istable(). 
IsUserData() - Tests if the object is userdata (including light userdata).  Mirrors lua_isuserdata(). 
IsCFunction() - Tests if the object is a C function.  Mirrors lua_iscfunction(). 
IsInteger() - Tests if the exact type of the object is a number.  See IsConvertibleToNumber() for the LuaObject equivalent of lua_isnumber(). 
IsNumber() - Tests if the exact type of the object is a number.  See IsConvertibleToNumber() for the LuaObject equivalent of lua_isnumber(). 
IsString() - Tests if the exact type of the object is a string.  See IsConvertibleToString() for the LuaObject equivalent of lua_isstring(). 
IsWString() - Tests if the exact type of the object is a wide string.  See IsConvertibleToWString() for the wide string equivalent of lua_isstring(). 
IsConvertibleToInteger() - Tests if the object is convertible to a number.  The object being tested can be a number, string, or wide string.  Mirrors lua_isnumber(). 
IsConvertibleToNumber() - Tests if the object is convertible to a number.  The object being tested can be a number, string, or wide string.  Mirrors lua_isnumber(). 
IsConvertibleToString() - Tests if the object is convertible to a string.  The object being tested can be a number or a string.  Mirrors lua_isstring(). 
IsConvertibleToWString() - Tests if the object is convertible to a wide string.  The object being tested can be a number or a wide string.  Mirrors lua_iswstring(), the wide character equivalent of lua_isstring(). 
IsFunction() - Tests if the object is a function.  Mirrors lua_isfunction(). 
IsNone() - Tests if the object is out of range on the stack.  Mirrors lua_isnone(). 
IsLightUserData() - Tests if the object is specifically light user data. 
IsBoolean() - Tests if the object is a boolean.  Mirrors lua_isboolean(). 
 
 
可以通过 Type()函数检查原始的真实类型 
Type()的返回值是 LuaStatue类的一个枚举类型 下面是这个枚举值
enum Types{    TNONE = (-1),    TNIL = 0,    TBOOLEAN = 1,    TLIGHTUSERDATA = 2,    TNUMBER = 3,    TSTRING = 4,    TTABLE = 5,    TFUNCTION = 6,    TUSERDATA = 7,    TTHREAD = 8,    TWSTRING = 9,}; 可以通过 LuaObject类的函数  TypeName()  获得到类型名 有点类似 lua_typename()
取值函数
如果实际类型不可以转换你所要取的类型 
 在 debug版本 都会触发assert
 
int ToInteger() - Mirrors lua_tonumber().  尝试从object对象内取出证书 即使实际类型为一个字符串
lua_Number ToNumber() - Mirrors lua_tonumber().  尝试从object对象内取出证书 即使实际类型为一个字符串 
const char* ToString() - Mirrors lua_tostring().  尝试取出字符串,如果实际类型为number number将被强制转换为string
const lua_WChar* ToWString() - Mirrors lua_towstring().  尝试取出 宽字符串,如果实际类型为number number将被强制转换为宽字符
int GetInteger() - 取出整数  如果实际类型不是number将触发assert
float GetFloat() -同上
double GetDouble() - Retrieves the double the object represents.  Asserts if the object is not of a numeric type. 
lua_Number GetNumber() - Retrieves the lua_Number the object represents.  Asserts if the object is not of a numeric type. 
const char* GetString() - Retrieves the string the object represents.  Asserts if the object is not a single byte string type. 
const lua_WChar* GetWString() - Retrieves the wide string the object represents.  Asserts if the object is not a double byte string type. 
lua_CFunction GetCFunction() - Retrieves the C function pointer the object represents.  Asserts if the object is not a C function. 
void* GetUserData() - Retrieves the userdata or light userdata the object represents.  Asserts if the object is not a userdata. 
void* GetLightUserData() - Retrieves the light userdata the object represents.  Asserts if the object is not a light userdata. 
bool GetBoolean() - Retrieves the boolean the object represents.  Asserts if the object is not a boolean convertible type. 

如果 LuaObject 是 ANSI 或 宽字符 字符串,可以通过 StrLen() 取得字符串的长度
ToStrLen() 函数可用于获取自动转换到字符串的number类型的长度   ToStrLen () 同 lua_strlen() 
 
如果 object 类型为 table,function,userdata 或者 light userdata 那么 可以通过 GetLuaPointer() 获得储存在lua内部的指针
LuaObject obj = state->GetGlobal("SomeVariable");if (obj.IsString()){    const char* str = obj.GetString();}//一个示例