error with Static Library code

hi all,
i'm learning the book "Teach Yourself Visual C++ 6 in 21 days" , and i'm in Chapter 16 - Creating Your Own Classes and Modules . I did everything like it said but i've an error. This Static Library project has 2 classes , 1 class , called CLine , is added from other project and 1 class , called CModArt , is added in this project .
So this is the code to creat new line in CModArt class :

Code:

---

void CModArt::NewLine()
{
        int lNumLines;
        int lCurLine;
        int nCurColor;
        UINT nCurWidth;
        CPoint pTo;
        CPoint pFrom;

        //Normalize the rectangle before determining the width and height
        m_rDrawArea.NormalizeRect();
        //Get the area width and height
        int lWidth = m_rDrawArea.Width();
        int lHeight = m_rDrawArea.Height();

        //Determine number of parts to this squiggle
        lNumLines = rand() % 100;
        //Are there any part in squiggle
        if (lNumLines > 0)
        {
                //Determine color
                nCurColor = rand() % 8;
                //Determine the pen width
                nCurWidth = (rand() % 8) + 1;
                //Determine the start point for the squiggle
                pFrom.x = (rand() % lWidth) + m_rDrawArea.left;
                pFrom.y = (rand() % lHeight) + m_rDrawArea.top;

                //Loop through number of sequents
                for (lCurLine=0; lCurLine<lNumLines; lCurLine++)
                {
                        pTo.x = ((rand() % 20) - 10) + pFrom.x;
                        pTo.y = ((rand() % 20) - 10) + pFrom.y;

                        //Creat a new line
                        //CLine *pLine = new CLine(pFrom, pTo, nCurWidth, m_crColors[nCurColor]);
                        CLine *pLine = new CLine(pFrom, pTo, m_crColors[nCurColor]);

                        try
                        {
                                //try to add new line
                                m_oaLines.Add(pLine);
                        }

                        //Check did we run into memory exception
                        catch (CMemoryException *perr)
                        {
                                //Notice user the message
                                AfxMessageBox("Out of memory", MB_ICONSTOP | MB_OK);
                                //Did we creat a new line
                                if (pLine)
                                {
                                        delete pLine;
                                        pLine = NULL;
                                }
                                //Delete the exception
                                perr->Delete();
                        }
                        //Set the starting point to the end point;
                        pFrom = pTo;
                }
        }
}

---

and this is the error :

Quote:

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...\ModArt.cpp(82) : error C2065: 'CLine' : undeclared identifier

---

and this is the 82 line :

Code:

---

CLine *pLine = new CLine(pFrom, pTo, m_crColors[nCurColor]);

---

Thanx 4 all ur helps!

> ...\ModArt.cpp(82) : error C2065: 'CLine' : undeclared identifier
Do you have a header file for the CLine class? It sounds like you need to:

Code:

---

#include "cline.h"

---

at the top of ModArt.cpp. Or if you don't have a header for CLine, I guess you'd have to include cline.cpp.

oh , i fixed this bug but i dont understand why . Because before that , I already have include "cline.h" in ModArt.cpp . But now when i also include "cline.h" in ModArt.h , it work gud?
so wat prob here cus i think i just need to include "cline.h" in ModArt.cpp , no need in ModArt.h ?

thanx 4 all ur helps!