绘制水平或垂直渐变矩阵

Graphics graphics( pDC->m_hDC );

CRgn rg2;
rg2.CreateRoundRectRgn(rcItem.left + 2,rcItem.top + 1,rcItem.right - 1,rcItem.bottom - 1,4,4);
Rect rc1(rcItem.left + 2,rcItem.top,rcItem.right - rcItem.left - 2,rcItem.top - rcItem.bottom - 2);
Color colors[] ={ Color(186,234,143),Color(239,255,208)}; //定义2种颜色 
REAL positions[] = {0.0f,0.5f};                //定义2种颜色距离起点位置 
LinearGradientBrush br(rc1,Color(186,234,143),Color(239,255,208),LinearGradientModeVertical);
br.SetInterpolationColors(colors,positions,2);
Region rgg(rg2);

graphics.FillRegion(&br,&rgg);