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---
# class (C++)
The `class` keyword declares a class type or defines an object of a class type.  
  
## Syntax  
  
```  
  
      [template-spec]  
       class [ms-decl-spec] [tag [: base-list ]]  
{  
   member-list  
} [declarators];  
[ class ] tag declarators;  
```  
  
#### Parameters  
 `template-spec`  
 Optional template specifications. For more information, refer to [Templates](templates-cpp.md).  
  
 `class`  
 The `class` keyword.  
  
 `ms-decl-spec`  
 Optional storage-class specification. For more information, refer to the [__declspec](../cpp/declspec.md) keyword.  
  
 `tag`  
 The type name given to the class. The tag becomes a reserved word within the scope of the class. The tag is optional. If omitted, an anonymous class is defined. For more information, see [Anonymous Class Types](../cpp/anonymous-class-types.md).  
  
 `base-list`  
 Optional list of classes or structures this class will derive its members from. See [Base Classes](../cpp/base-classes.md) for more information. Each base class or structure name can be preceded by an access specifier ([public](../cpp/public-cpp.md), [private](../cpp/private-cpp.md), [protected](../cpp/protected-cpp.md)) and the [virtual](../cpp/virtual-cpp.md) keyword. See the member-access table in [Controlling Access to Class Members](member-access-control-cpp.md) for more information.  
  
 `member-list`  
 List of class members. Refer to [Class Member Overview](../cpp/class-member-overview.md) for more information.  
  
 `declarators`  
 Declarator list specifying the names of one or more instances of the class type. Declarators may include initializer lists if all data members of the class are `public`. This is more common in structures, whose data members are `public` by default, than in classes. See [Overview of Declarators](../cpp/overview-of-declarators.md) for more information.  
  
## Remarks  
 For more information on classes in general, refer to one of the following topics:  
  
-   [struct](../cpp/struct-cpp.md)  
  
-   [union](../cpp/unions.md)  
  
-   [__multiple_inheritance](../cpp/inheritance-keywords.md)  
  
-   [__single_inheritance](../cpp/inheritance-keywords.md)  
  
-   [__virtual_inheritance](../cpp/inheritance-keywords.md)  
  
 For information on managed classes and structs, see [Classes and Structs](../windows/classes-and-structs-cpp-component-extensions.md)  
  
## Example  
  
```  
// class.cpp  
// compile with: /EHsc  
// Example of the class keyword  
// Exhibits polymorphism/virtual functions.  
  
#include <iostream>  
#include <string>  
#define TRUE = 1  
using namespace std;  
  
class dog  
{  
public:  
   dog()  
   {  
      _legs = 4;  
      _bark = true;  
   }  
  
   void setDogSize(string dogSize)  
   {  
      _dogSize = dogSize;  
   }  
   virtual void setEars(string type)      // virtual function  
   {  
      _earType = type;  
   }  
  
private:  
   string _dogSize, _earType;  
   int _legs;  
   bool _bark;  
  
};  
  
class breed : public dog  
{  
public:  
   breed( string color, string size)  
   {  
      _color = color;  
      setDogSize(size);  
   }  
  
   string getColor()  
   {  
      return _color;  
   }  
  
   // virtual function redefined  
   void setEars(string length, string type)  
   {  
      _earLength = length;  
      _earType = type;  
   }  
  
protected:  
   string _color, _earLength, _earType;  
};  
  
int main()  
{  
   dog mongrel;  
   breed labrador("yellow", "large");  
   mongrel.setEars("pointy");  
   labrador.setEars("long", "floppy");  
   cout << "Cody is a " << labrador.getColor() << " labrador" << endl;  
}  
```  
  
## See Also  
 [Keywords](../cpp/keywords-cpp.md)   
 [Classes and Structs](../cpp/classes-and-structs-cpp.md)