How can I get the class name from a C object

Question

Is it possible to get the object name too    include lt cstdio gt   class one   public      int no of students      one     no of students   0        void new admission     no of students          int main         one A      for int i   0  i  lt  99  i              A new admission              cout lt  lt  class  lt  lt  classname  lt  lt     lt  lt  objectname  lt  lt  has            lt  lt A no of students lt  lt   students       where I can fetch the names  something like    classname    A classname     one  objectname    A objectname     A   Does C   provide any mechanism to achieve this

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use typeid class  name     illustratory code assuming all includes namespaces etc   include  lt iostream gt   include  lt typeinfo gt  using namespace std   struct A    int main       cout  lt  lt  typeid A  name           It is important to remember that this   gives an implementation defined names    As far as I know  there is no way to get the name of the object at run time reliably e g   A  in your code   EDIT 2    include  lt typeinfo gt   include  lt iostream gt   include  lt map gt  using namespace std    struct A     struct B      map lt const type info   string gt  m   int main        m  amp typeid A      A              Registration here     m  amp typeid B      B              Registration here      A a      cout  lt  lt  m  amp typeid a

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Do you want  classname  to be  one  and  objectname  to be  A    If so  this is not possible  These names are only abstractions for the programmer  and aren t actually used in the binary code that is generated  You could give the class a static variable classname  which you set to  one  and a normal variable objectname which you would assign either directly  through a method or the constructor  You can then query these methods for the class and object names

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You can display the name of a variable by using the preprocessor  For instance   include  lt iostream gt   define quote x   x class one     int main        one A      std  cout lt  lt typeid A  name   lt  lt   t  lt  lt  quote A   lt  lt   n       return 0      outputs   3one    A   on my machine  The   changes a token into a string  after preprocessing the line is  std  cout lt  lt typeid A  name   lt  lt   t  lt  lt   A   lt  lt   n     Of course if you do something like  void foo one B       std  cout lt  lt typeid B  name   lt  lt   t  lt  lt  quote B   lt  lt   n     int main        one A      foo A       return 0      you will get  3one B   as the compiler doesn t keep track of all of the variable s names   As it happens in gcc the result of typeid   name   is the mangled class name  to get the demangled version use   include  lt iostream gt   include  lt cxxabi h gt   define quote x   x template  lt typename foo typename bar gt  class one     int main        one lt int one lt double  int gt   gt  A      int status      char   demangled   abi    cxa demangle typeid A  name   0 0  amp status       std  cout lt  lt demangled lt  lt   t  lt  lt  quote A   lt  lt   n       free demangled       return 0      which gives me  one lt int  one lt double  int gt   gt  A   Other compilers may use different naming schemes

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You can try this   template lt typename T gt  inline const char  getTypeName       return typeid T  name        define DEFINE TYPE NAME type  type name       template lt  gt                                    inline const char  getTypeName lt type gt            return type name                              DEFINE TYPE NAME int   int   DEFINE TYPE NAME float   float   DEFINE TYPE NAME double   double   DEFINE TYPE NAME std  string   string   DEFINE TYPE NAME bool   bool   DEFINE TYPE NAME uint32 t   uint   DEFINE TYPE NAME uint64 t   uint      add your custom types  definitions   And call it like that   void main      std  cout  lt  lt  getTypeName lt int gt

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Just write simple template   template lt typename T gt  const char  getClassName T      return typeid T  name       struct A    a   void main        std  cout  lt  lt  getClassName a

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To get class name without mangling stuff you can use func macro in constructor   class MyClass       const char  name      MyClass             name     func

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You could try using  typeid    This doesn t work for  object  name but YOU know the object name so you ll just have to store it somewhere   The Compiler doesn t care what you namned an object   Its worth bearing in mind  though  that the output of typeid is a compiler specific thing so even if it produces what you are after on the current platform it may not on another   This may or may not be a problem for you   The other solution is to create some kind of template wrapper that you store the class name in   Then you need to use partial specialisation to get it to return the correct class name for you   This has the advantage of working compile time but is significantly more complex   Edit  Being more explicit  template lt  typename Type  gt  class ClassName   public      static std  string name                 return  Unknown              Then for each class somethign liek the following   template lt  gt  class ClassName lt MyClass gt    public      static std  string name                 return  MyClass              Which could even be macro d as follows    define DefineClassName  className       template lt  gt  class ClassName lt className gt        public        static std  string name                     return  className                   Allowing you to  simply  do  DefineClassName  MyClass      Finally to Get the class name you d do the following   ClassName lt  MyClass  gt   name      Edit2   Elaborating further you d then need to put this  DefineClassName  macro in each class you make and define a  classname  function that would call the static template function   Edit3   And thinking about it     Its obviously bad posting first thing in the morning as you may as well just define a member function  classname    as follows   std  string classname          return  MyClass       which can be macro d as follows   DefineClassName  className     std  string classname               return  className        Then you can simply just drop  DefineClassName  MyClass      into the class as you define it

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An improvement for  Chubsdad answer     main cpp  using namespace std   int main    A a  a run         A h class A  public   A       void run         A cpp  include  lt iostream gt   include  lt typeinfo gt  void A  run       cout  lt  lt   string typeid this  name        Which will print   class A

[c++] How can I get the class name from a C++ object?

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