myview.cpp

来自「由吕军等人著的《Visual C++ 与面向对象程序设计教程》课后习题的源代码」· C++ 代码 · 共 164 行

// MyView.cpp : implementation of the CMyView class
//

#include "stdafx.h"
#include "My.h"

#include "MyDoc.h"
#include "MyView.h"

#include "Math.h"

#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif

/////////////////////////////////////////////////////////////////////////////
// CMyView

IMPLEMENT_DYNCREATE(CMyView, CView)

BEGIN_MESSAGE_MAP(CMyView, CView)
	//{{AFX_MSG_MAP(CMyView)
		// NOTE - the ClassWizard will add and remove mapping macros here.
		//    DO NOT EDIT what you see in these blocks of generated code!
	//}}AFX_MSG_MAP
	// Standard printing commands
	ON_COMMAND(ID_FILE_PRINT, CView::OnFilePrint)
	ON_COMMAND(ID_FILE_PRINT_DIRECT, CView::OnFilePrint)
	ON_COMMAND(ID_FILE_PRINT_PREVIEW, CView::OnFilePrintPreview)
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CMyView construction/destruction

CMyView::CMyView()
{
	// TODO: add construction code here

}

CMyView::~CMyView()
{
}

BOOL CMyView::PreCreateWindow(CREATESTRUCT& cs)
{
	// TODO: Modify the Window class or styles here by modifying
	//  the CREATESTRUCT cs

	return CView::PreCreateWindow(cs);
}

/////////////////////////////////////////////////////////////////////////////
// CMyView drawing

void CMyView::OnDraw(CDC* pDC)
{
	CMyDoc* pDoc = GetDocument();
	ASSERT_VALID(pDoc);
	// TODO: add draw code for native data here

	//画sin(x)曲线
	const double PI = 3.14159265359;
	const double dbYMax = 1.0;
	const double dbYMin = -1.0;
	const double dbXMin = 0.0;
	const double dbXMax = 2 * PI;
	const int iPt = 200;

	const int xOrg = 50;
	const int yOrg = 350;
	const int xMax = 700;
	const int yMin = 20;

	//换算数据并画出折线
	double dbXRatio = (xMax-xOrg)/(dbXMax-dbXMin);
	double dbYRatio = (yOrg-yMin)/(dbYMax-dbYMin);

	int x = xOrg;
	int y = yOrg;
	pDC->MoveTo(x,y);
	
	for(int i=0; i<=iPt; i++)
	{
		x = (int) (dbXRatio * (dbXMax/iPt*i-dbXMin) + xOrg);
		y = (int) (yOrg - dbYRatio * (sin(dbXMax/iPt*i)-dbYMin));
		pDC->LineTo(x,y);
	}

	//画轴
	/* x轴在中央

	x = (int) (dbXRatio * 0 + xOrg);
	y = (int) (yOrg - dbYRatio * (sin(0.0)-dbYMin));
	pDC->MoveTo(x, y);
	
	x = (int) (dbXRatio * dbXMax + xOrg);
	y = (int) (yOrg - dbYRatio * (sin(dbXMax)-dbYMin));
	pDC->LineTo(x, y);

	*/
	//如需x轴在中央，注释掉下2行代码
	pDC->MoveTo(xOrg,yOrg);
	pDC->LineTo(xMax,yOrg);
	pDC->MoveTo(xOrg,yOrg);
	pDC->LineTo(xOrg,yMin);

	//写轴标题
	x = (xMax-xOrg)/2;
	y = yOrg + 10;
	pDC->TextOut(x, y, "X");

	x = xOrg - 20;
	y = (yOrg - yMin)/2;
	pDC->TextOut(x, y, "Y");
	

}

/////////////////////////////////////////////////////////////////////////////
// CMyView printing

BOOL CMyView::OnPreparePrinting(CPrintInfo* pInfo)
{
	// default preparation
	return DoPreparePrinting(pInfo);
}

void CMyView::OnBeginPrinting(CDC* /*pDC*/, CPrintInfo* /*pInfo*/)
{
	// TODO: add extra initialization before printing
}

void CMyView::OnEndPrinting(CDC* /*pDC*/, CPrintInfo* /*pInfo*/)
{
	// TODO: add cleanup after printing
}

/////////////////////////////////////////////////////////////////////////////
// CMyView diagnostics

#ifdef _DEBUG
void CMyView::AssertValid() const
{
	CView::AssertValid();
}

void CMyView::Dump(CDumpContext& dc) const
{
	CView::Dump(dc);
}

CMyDoc* CMyView::GetDocument() // non-debug version is inline
{
	ASSERT(m_pDocument->IsKindOf(RUNTIME_CLASS(CMyDoc)));
	return (CMyDoc*)m_pDocument;
}
#endif //_DEBUG

/////////////////////////////////////////////////////////////////////////////
// CMyView message handlers