blocks|key|679649|text|不，您不能获得指向C%2B%2B类方法的指针(除非该方法被声明为静态)。原因是一个类方法总是有一个指针this，一个指向类实例的指针。但是如果您通过指针调用该方法，则该指针无法封装this指针，然后将不会附加任何实例，因此此行为是不合法的。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|679650|entityMap^0|1B|4|2E|4|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]|$9|K|A|L|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|M|8|@]|D|@]|E|$]]]|G|$]]

No, you can't get a pointer to a C++ class method (unless the method is declared static). The reason is that a class method always has the pointer <code>this</code>, a pointer to the class instance. But were you to call the method through a pointer, that pointer could not encapsulate the <code>this</code> pointer, and then then there would be no instance attached, and therefore this behavior is not legal.

blocks|key|680527|text|虽然不完全符合您的要求，但如果您可以使用C%2B%2B11，以下内容可能会满足您的需求(未经测试)：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|680528|std::function<int(double*,+double*,+int,+int,+void*)>
++some_function_of(Some_class&+obj)
{
++return+[&](double*+a,+double*+b,+int+c,+int+d,+void*+e){
++++return+obj.some_func(a,+b,+c,+d,+e);+};
}|code-block|syntax|javascript|680529|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

While not exactly what you requested, if you can use C++11 the following might nevertheless suit your needs (untested):

<pre><code>std::function&lt;int(double*, double*, int, int, void*)&gt;
 some_function_of(Some_class&amp; obj)
{
 return [&amp;](double* a, double* b, int c, int d, void* e){
 return obj.some_func(a, b, c, d, e); };
}
</code></pre>

blocks|key|681256|text|您可以编写某种类型的包装器，它既可以使用函数也可以使用方法作为参数。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|681257|我使用了以下类来启动函数(它在我的一个SDL程序中使用)：|681258|class+CallbackFunction+{
public:
++++//+Constructor,+copy+constructor+and+destructor

++++virtual+int+execute(+SDL_keysym*+keysym)+const;
++++virtual+int+operator()(+SDL_keysym*+keysym)+const;

protected:
++++int(+*callback)(+SDL_keysym*));
}

int+CallbackFunction::execute(+SDL_keysym*+keysym)+const{
++++return+callback(keysym);
}

int+CallbackFunction::operator()(+SDL_keysym*+keysym)+const{
++++return+callback(+keysym);
}|code-block|syntax|javascript|681259|还有这个“方法”的扩展：|681260|template<class+T>
class+CallbackMethod+:+public+CallbackFunction+{
public:
++++//+Constructor,+copy+constructor+and+destructor
++++CallbackMethod(+T+*object,+int(T::*callback)(+SDL_keysym*+keysym));

++++int+execute(+SDL_keysym*+keysym)+const;
++++int+operator()(SDL_keysym*+keysym)+const;

protected:
++++T+*object;
++++int(T::*method)(+SDL_keysym*+keysym);
};

//+Object+initialization+(constructor)
template<class+T>
CallbackMethod<T>::CallbackMethod(+T+*object,+int(T::*callback)(+SDL_keysym*+keysym)):
++++CallbackFunction(+NULL),object(object),method(callback){
}


//+Responsible+for+executing
template<class+T>
int+CallbackMethod<T>::execute(+SDL_keysym*+keysym)+const+{
++++return+(object->*method)(keysym);
}
template<class+T>
int+CallbackMethod<T>::operator()(+keysym)+const+{
++++return+(object->*method)(+keysym);
}|681261|然后将其用作：|681262|CallbackFunction+*callback;
callback+=+new+CallbackFunction(+myFunction);
callback+=+new+CallbackMethod<A>(+instanceOfA,+instanceOfA::myMethod);
callback+=+new+CallbackMethod(+instanceOfB,+instanceOfB::myMethod);
...
callback(+keysym);|681263|我发现宏是这样的：|681264|CALLBACK(object,method)+new+CallbackMethod<typeof(*object)>(+object,+&method)|681265|非常有用|681266|entityMap^0|0|0|0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Y|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|Z|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|10|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|11|8|@]|9|@]|A|$]]|$1|K|3|L|5|F|7|12|8|@]|9|@]|A|$G|H]]|$1|M|3|N|5|6|7|13|8|@]|9|@]|A|$]]|$1|O|3|P|5|F|7|14|8|@]|9|@]|A|$G|H]]|$1|Q|3|R|5|6|7|15|8|@]|9|@]|A|$]]|$1|S|3|T|5|F|7|16|8|@]|9|@]|A|$G|H]]|$1|U|3|V|5|6|7|17|8|@]|9|@]|A|$]]|$1|W|3|-4|5|6|7|18|8|@]|9|@]|A|$]]]|X|$]]

You may write some kind of Wrapper which is able to use both function or method as parameter.

I used following classes for launching functions (it was used in one my SDL program):

<pre><code>class CallbackFunction {
public:
 // Constructor, copy constructor and destructor

 virtual int execute( SDL_keysym* keysym) const;
 virtual int operator()( SDL_keysym* keysym) const;

protected:
 int( *callback)( SDL_keysym*));
}

int CallbackFunction::execute( SDL_keysym* keysym) const{
 return callback(keysym);
}

int CallbackFunction::operator()( SDL_keysym* keysym) const{
 return callback( keysym);
}
</code></pre>

And this extension for "methods":

<pre><code>template&lt;class T&gt;
class CallbackMethod : public CallbackFunction {
public:
 // Constructor, copy constructor and destructor
 CallbackMethod( T *object, int(T::*callback)( SDL_keysym* keysym));

 int execute( SDL_keysym* keysym) const;
 int operator()(SDL_keysym* keysym) const;

protected:
 T *object;
 int(T::*method)( SDL_keysym* keysym);
};

// Object initialization (constructor)
template&lt;class T&gt;
CallbackMethod&lt;T&gt;::CallbackMethod( T *object, int(T::*callback)( SDL_keysym* keysym)):
 CallbackFunction( NULL),object(object),method(callback){
}


// Responsible for executing
template&lt;class T&gt;
int CallbackMethod&lt;T&gt;::execute( SDL_keysym* keysym) const {
 return (object-&gt;*method)(keysym);
}
template&lt;class T&gt;
int CallbackMethod&lt;T&gt;::operator()( keysym) const {
 return (object-&gt;*method)( keysym);
}
</code></pre>

And then use it as:

<pre><code>CallbackFunction *callback;
callback = new CallbackFunction( myFunction);
callback = new CallbackMethod&lt;A&gt;( instanceOfA, instanceOfA::myMethod);
callback = new CallbackMethod&lt;B&gt;( instanceOfB, instanceOfB::myMethod);
...
callback( keysym);
</code></pre>

I found macro as this:

<pre><code>CALLBACK(object,method) new CallbackMethod&lt;typeof(*object)&gt;( object, &amp;method)
</code></pre>

really useful

blocks|key|681344|text|我使用了Boost库。我在代码中包含了"boost/bind.hpp“。则名为"fn“的方法可以定义为|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|681345|auto+fn+=boost：：bind(类名：：方法名，classInstanceName，boost::placeholders::_1)；|681346|entityMap|0|LINK|mutability|MUTABLE|url|http://www.boost.org/^0|4|5|0|0|0^^$0|@$1|2|3|4|5|6|7|N|8|@]|9|@$A|O|B|P|1|Q]]|C|$]]|$1|D|3|E|5|6|7|R|8|@]|9|@]|C|$]]|$1|F|3|-4|5|6|7|S|8|@]|9|@]|C|$]]]|G|$H|$5|I|J|K|C|$L|M]]]]

I used the <a href="http://www.boost.org/" rel="nofollow noreferrer">Boost</a> library. I included "boost/bind.hpp" in my code. Then a method named "fn" can be defined as

auto fn = boost::bind(ClassName::methodName, classInstanceName, boost::placeholders::_1);

Here is the problem: 

1) I have a class like so:

<pre><code>class some_class
{
public:
 some_type some_value;
 int some_function(double *a, double *b, int c, int d, void *e);
};
</code></pre>

2) Inside <code>some_function</code>, I use <code>some_values</code> from <code>some_class</code> object to get a result.

3) So, I have a concrete object and I want to get a pointer to this object <code>some_function</code>.

Is it possible? I can't use <code>some_fcn_ptr</code> because the result of this function depends on the concrete <code>some_value</code> of an object. 

How can I get a pointer to <code>some_function</code> of an object? Thanks.

<pre><code>typedef int (Some_class::*some_fcn_ptr)(double*, double*, int, int, void*);
</code></pre>

Get a pointer to object's member function

以下是问题所在：1)我有一个这样的类：class some_class{public:    some_type some_value;    int some_function(double *a, double *b, int c, int d, void *e);};2)在some_function中，我使用来自...

问获取指向对象成员函数的指针
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