1.头文件里定义一个画刷：

CBrush m_brushColor;

2.在OnInitDialog()初始化时创建画刷，并设置实际的颜色：

m_brushColor.CreateSolidBrush ( RGB ( 100, 100, 255 ));//初始化颜色画刷

3.通过类向导添加afx_msg HBRUSH OnCtlColor()函数，并返回颜色刷子：

HBRUSH CxxxDlg::OnCtlColor(CDC* pDC, CWnd* pWnd, UINT nCtlColor) 
{
	HBRUSH hbr = CDialog::OnCtlColor(pDC, pWnd, nCtlColor);
	
	// TODO: Change any attributes of the DC here
	if(nCtlColor ==CTLCOLOR_DLG)
	return m_brushColor;  //返回颜色刷子 
}