Question

I think I’ve declared a Vector with an object correctly. But, I don’t know how to access it’s members when looping with Iterator.

In my code, the line —>> cout << ‘ ‘ << *Iter;

How do I print the contents of the members? Like *Iter.m_PackLine ???

Not sure if I used the correct terminology, but appreciate the help! Thanks

class CFileInfo {   public:       std::string m_PackLine;       std::string m_FileDateTime;       int m_NumDownloads; };  void main() {   CFileInfo packInfo;    vector<CFileInfo, CFileInfo&> unsortedFiles;   vector<CFileInfo, CFileInfo&>::iterator Iter;    packInfo.m_PackLine = 'Sample Line 1';   packInfo.m_FileDateTime = '06/22/2008 04:34';   packInfo.m_NumDownloads = 0;   unsortedFiles.push_back(packInfo);    packInfo.m_PackLine = 'Sample Line 2';   packInfo.m_FileDateTime = '12/05/2007 14:54';   packInfo.m_NumDownloads = 1;   unsortedFiles.push_back(packInfo);   for (Iter = unsortedFiles.begin(); Iter != unsortedFiles.end(); Iter++ )  {     cout << ' ' << *Iter; // !!! THIS IS WHERE I GET STUMPED     // How do I output values of the object members?   } }  // end main 

Answer 1

cout << ' ' << *Iter; 

will only work if CFileInfo has an overloaded operator<< that can output your struct. You can output individual members of the struct instead like this:

cout << ' ' << Iter->m_PackLine; 

Alternatively, the following is equivalent to that:

cout << ' ' << (*Iter).m_PackLine; 

You have to put parentheses around *Iter, since the member-access operator binds thighter otherwise.

On a side-node, make your main function return int instead of void. making it return void is not valid in C++.

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You declare the vector like this:

vector<CFileInfo, CFileInfo&> unsortedFiles; 

The second argument to vector should be another thing. It’s not needed for your code to give the vector a second argument at all. Just use this:

vector<CFileInfo> unsortedFiles; 

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Another thing i noticed is you increment the iterator using Iter++ (called postfix increment). For iterators, always prefer ++Iter, which is called prefix increment.