GDI+是微软在Windows2000以后的操作系统中提供的新接口，它是基于面向对象的，而GDI是基于函数的。
建议大家使用GDI+画图，GDI+使用简单，下面是GDI+与GDI使用的方式。
GDI+使用说明：
void CDlgClassroom::OnPaint()
{
if (IsIconic())
{
CPaintDC dc(this); // device context for painting
SendMessage(WM_ICONERASEBKGND, reinterpret_cast<WPARAM>(dc.GetSafeHdc()), 0);
// Center icon in client rectangle
int cxIcon = GetSystemMetrics(SM_CXICON);
int cyIcon = GetSystemMetrics(SM_CYICON);
CRect rect;
GetClientRect(&rect);
int x = (rect.Width() - cxIcon + 1) / 2;
int y = (rect.Height() - cyIcon + 1) / 2;
// Draw the icon
dc.DrawIcon(x, y, m_hIcon);
}
else
{
CPaintDC dc(this);
CRect rect;
GetClientRect(&rect);//对话框当前位置
Graphics graphics(dc.m_hDC);
ImageAttributes imAtt;
imAtt.SetWrapMode(WrapModeTile); //拉伸图片
//拉伸图片
Bitmap backgroundtop(L".\\classroom\\class_toolbar_top.png"); //加载PNG图片
graphics.DrawImage(&backgroundtop,Rect(0,0,rect.Width(),34),
0, 0,backgroundtop.GetWidth(),backgroundtop.GetHeight(),UnitPixel,&imAtt);
///////////////平铺背景图
// Bitmap backgroundmiddle(L".\\room\\BgBlackboard.png");//加载PNG图片
// TextureBrush brush(&backgroundmiddle, WrapModeTile/*FlipXY*/ );
// graphics.FillRectangle(&brush, RectF(0.0f, 0.0f,rect.Width(),rect.Height()));
CDialog::OnPaint();
}
}
GDI使用：
GDI操作起来就比较繁琐。
voidCDlgClassroom::OnPaint()
{
if (IsIconic())
{
CPaintDC dc(this); // device context for painting
SendMessage(WM_ICONERASEBKGND, reinterpret_cast<WPARAM>(dc.GetSafeHdc()), 0);
// Center icon in client rectangle
int cxIcon = GetSystemMetrics(SM_CXICON);
int cyIcon = GetSystemMetrics(SM_CYICON);
CRect rect;
GetClientRect(&rect);
intx = (rect.Width() - cxIcon + 1) / 2;
inty = (rect.Height() - cyIcon + 1) / 2;
// Draw the icon
dc.DrawIcon(x, y, m_hIcon);
}
else
{
CPaintDC dc(this);
CRect rect;
GetClientRect(&rect);//对话框当前位置
//平铺图片
CDC MemDC;
CBitmap cbitmap;
CBitmap* pOldBmp = NULL;
HBITMAP hBitmap;
CDC * pDC = GetDC();
//顶部背景图
Bitmap backgroundtop(L".\\classroom\\class_toolbar_top.png"); //加载PNG图片
backgroundtop.GetHBITMAP(Color(0,0,0),&hBitmap); // Bitmap To HBITMAP
CBitmap* cBitmap = CBitmap::FromHandle(hBitmap); // HBITMAP To CBitmap *
MemDC.CreateCompatibleDC(pDC); // 显示图片
pOldBmp = MemDC.SelectObject(cBitmap);
dc.StretchBlt(0,0,rect.Width(),34, &MemDC, 0, 0,backgroundtop.GetWidth() ,backgroundtop.GetHeight(),SRCCOPY);
MemDC.SelectObject(pOldBmp);//releaseDC
MemDC.DeleteDC();
cBitmap->DeleteObject();
CDialog::OnPaint();
}
}