Sams Teach Yourself C++ in 21 Days

Advanced Inheritance 557

16

138: private:

139: PartNode * pHead;

140: int itsCount;

141: static PartsList GlobalPartsList;

142: };

143:

144: PartsList PartsList::GlobalPartsList;

145:

146:

147: PartsList::PartsList():

148: pHead(0),

149: itsCount(0)

150: {}

151:

152: PartsList::~PartsList()

153: {

154: delete pHead;

155: }

156:

157: Part* PartsList::GetFirst() const

158: {

159: if (pHead)

160: return pHead->GetPart();

161: else

162: return NULL; // error catch here

163: }

164:

165: Part * PartsList::operator[](int offSet) const

166: {

167: PartNode* pNode = pHead;

168:

169: if (!pHead)

170: return NULL; // error catch here

171:

172: if (offSet > itsCount)

173: return NULL; // error

174:

175: for (int i=0;i<offSet; i++)

176: pNode = pNode->GetNext();

177:

178: return pNode->GetPart();

179: }

180:

181: Part* PartsList::Find(

182: int & position,

183: int PartNumber) const

184: {

185: PartNode * pNode = 0;

186: for (pNode = pHead, position = 0;

187: pNode!=NULL;

188: pNode = pNode->GetNext(), position++)

189: {

LISTING16.5 continued