How to set richedit ctrl full line's background color?

[fantasy1215]

I've googled to set the background color of the text using following code

CHARFORMAT2 cf;
cf.cbSize = sizeof(cf);
cf.dwMask = CFM_BACKCOLOR;
cf.dwEffects = CFE_PROTECTED;
cf.crBackColor = m_crBkTwo;
m_edText.SendMessage(EM_SETCHARFORMAT, (WPARAM)SCF_SELECTION|SCF_WORD,
	(LPARAM)&cf);

But the effect is just setting background color of inserting text, not full line,
Is there some way to set full line using the color?