Question

VC++里的DC和CDC 有什么功能和参数

Answer 1

设备内容属性 默认值 修改该值的函数 取得该值的函数
Mapping Mode MM_TEXT SetMapMode GetMapMode
Window Origin (0,0) SetWindowOrgExOffsetWindowOrgEx GetWindowOrgEx
Viewport Origin (0,0) SetViewportOrgEx
OffsetViewportOrgEx GetViewportOrgEx
Window Extents (1,1) SetWindowExtEx SetMapMode ScaleWindowExtEx GetWindowExtEx
Viewport Extents (1,1) SetViewportExtEx SetMapMode ScaleViewportExtEx GetViewportExtEx
Pen BLACK_PEN SelectObject SelectObject
Brush WHITE_BRUSH SelectObject SelectObject
Font SYSTEM_FONT SelectObject SelectObject
Bitmap None SelectObject SelectObject
Current Position (0,0) MoveToEx LineTo PolylineTo PolyBezierTo ArcTo GetCurrentPositionEx
Background Mode OPAQUE SetBkMode GetBkMode
Background Color White SetBkColor GetBkColor
Text Color Black SetTextColor GetTextColor
Drawing Mode R2_COPYPEN SetROP2 GetROP2
Stretching Mode BLACKONWHITE SetStretchBltMode GetStretchBltMode
Polygon Fill Mode ALTERNATE SetPolyFillMode GetPolyFillMode
Intercharacter Spacing 0 SetTextCharacterExtra GetTextCharacterExtra
Brush Origin (0,0) SetBrushOrgEx GetBrushOrgEx
Clipping Region None SelectObject SelectClipRgn IntersectClipRgn OffsetClipRgn ExcludeClipRect SelectClipPath GetClipBox

Answer 2

没有DC这个东西，只有HDC句柄
CDC是mfc对HDC进行了封装
CDC是一个类，封装了GDI的所以操作函数。