//============================================================================= // File: param.h // Contents: Declarations for DwParameter // Maintainer: Doug Sauder // WWW: http://www.fwb.gulf.net/~dwsauder/mimepp.html // // Copyright (c) 1996, 1997 Douglas W. Sauder // All rights reserved. // // IN NO EVENT SHALL DOUGLAS W. SAUDER BE LIABLE TO ANY PARTY FOR DIRECT, // INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT OF // THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF DOUGLAS W. SAUDER // HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. // // DOUGLAS W. SAUDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, BUT // NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A // PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS ON AN "AS IS" // BASIS, AND DOUGLAS W. SAUDER HAS NO OBLIGATION TO PROVIDE MAINTENANCE, // SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. // //============================================================================= #ifndef DW_PARAM_H #define DW_PARAM_H #ifndef DW_CONFIG_H #include #endif #ifndef DW_STRING_H #include #endif #ifndef DW_MSGCMP_H #include #endif //============================================================================= //+ Name DwParameter -- Class representing a MIME field body parameter //+ Description //. {\tt DwParameter} represents the {\it parameter} component of the //. Content-Type header field as described in RFC-2045. A parameter //. consists of an attribute/value pair. {\tt DwParameter} has member //. functions for getting or setting a parameter's attribute and value. //. //. A {\tt DwParameter} object may be included in a list of {\tt DwParameter} //. objects. You can get the next {\tt DwParameter} object in the list by //. calling the member function {\tt Next()}. //============================================================================= // Last modified 1997-08-13 //+ Noentry ~DwParameter _PrintDebugInfo class DW_EXPORT DwParameter : public DwMessageComponent { friend class DwMediaType; public: DwParameter(); DwParameter(const DwParameter& aParam); DwParameter(const DwString& aStr, DwMessageComponent* aParent=0); //. The first constructor is the default constructor, which sets the //. {\tt DwParameter} object's string representation to the empty string //. and sets its parent to NULL. //. //. The second constructor is the copy constructor, which copies the //. string representation, attribute, and value from {\tt aParam}. //. The parent of the new {\tt DwParameter} object is set to NULL. //. //. The third constructor copies {\tt aStr} to the {\tt DwParameter} //. object's string representation and sets {\tt aParent} as its parent. //. The virtual member function {\tt Parse()} should be called immediately //. after this constructor in order to parse the string representation. //. Unless it is NULL, {\tt aParent} should point to an object of a class //. derived from {\tt DwMediaType}. virtual ~DwParameter(); const DwParameter& operator = (const DwParameter& aParam); //. This is the assignment operator. virtual void Parse(); //. This virtual function, inherited from {\tt DwMessageComponent}, //. executes the parse method for {\tt DwParameter} objects. //. It should be called immediately after the string representation //. is modified and before the parts of the broken-down //. representation are accessed. virtual void Assemble(); //. This virtual function, inherited from {\tt DwMessageComponent}, //. executes the assemble method for {\tt DwParameter} objects. //. It should be called whenever one of the object's attributes //. is changed in order to assemble the string representation from //. its broken-down representation. It will be called //. automatically for this object by the parent object's //. {\tt Assemble()} member function if the is-modified flag is set. virtual DwMessageComponent* Clone() const; //. This virtual function, inherited from {\tt DwMessageComponent}, //. creates a new {\tt DwParameter} on the free store that has the same //. value as this {\tt DwParameter} object. The basic idea is that of //. a ``virtual copy constructor.'' const DwString& Attribute() const; //. Returns the attribute contained by this parameter. void SetAttribute(const DwString& aAttribute); //. Sets the attribute contained by this parameter. const DwString& Value() const; //. Returns the value contained by this parameter. void SetValue(const DwString& aValue, bool forceNoQuotes=false); //. Sets the value contained by this parameter. DwParameter* Next() const ; //. Returns the next {\tt DwParameter} object in the list. void SetNext(DwParameter* aParam); //. Returns the next {\tt DwParameter} object in the list. Since //. {\tt DwMediaType} has member functions for adding {\tt DwParameter} //. objects to its list, you should avoid using this function. static DwParameter* NewParameter(const DwString& aStr, DwMessageComponent* aParent); //. Creates a new {\tt DwParameter} object on the free store. //. If the static data member {\tt sNewParameter} is NULL, //. this member function will create a new {\tt DwParameter} //. and return it. Otherwise, {\tt NewParameter()} will call //. the user-supplied function pointed to by {\tt sNewParameter}, //. which is assumed to return an object from a class derived from //. {\tt DwParameter}, and return that object. //+ Var sNewParameter static DwParameter* (*sNewParameter)(const DwString&, DwMessageComponent*); //. If {\tt sNewParameter} is not NULL, it is assumed to point to a //. user-supplied function that returns an object from a class derived from //. {\tt DwParameter}. private: DwString mAttribute; DwString mValue; bool mForceNoQuotes; DwParameter* mNext; static const char* const sClassName; public: virtual void PrintDebugInfo(std::ostream& aStrm, int aDepth=0) const; //. This virtual function, inherited from {\tt DwMessageComponent}, //. prints debugging information about this object to {\tt aStrm}. //. It will also call {\tt PrintDebugInfo()} for any of its child //. components down to a level of {\tt aDepth}. //. //. This member function is available only in the debug version of //. the library. virtual void CheckInvariants() const; //. Aborts if one of the invariants of the object fails. Use this //. member function to track down bugs. //. //. This member function is available only in the debug version of //. the library. protected: void _PrintDebugInfo(std::ostream& aStrm) const; }; #endif