beginPath beginShape bezierTo clearCachedBitmap clearRect clipPath clipRect closePath drawBitmap drawEllipse drawHandle drawLine drawPath drawRect drawTextAt drawTextAt endShape lineTo moveTo quadTo restoreClip saveClip setBrush setPen ~GiCanvas

clearRect() virtual void GiCanvas::clearRect ( float  x, float  y, float  w, float  h  ) pure virtual Clear `rect' (that is, set the region within the rect to transparent). 在 GiGdipCanvas, GiShapeAdapter, GiCanvasAdapter, GiRecordCanvas , 以及 GiSvgCanvas 内被实现. 这是这个函数的调用关系图: