var ScreenDepth = 0;	// 指定当前屏幕深度;
var ScreenDepthMax = 3;	// 指定屏幕深度标值,下标按零开始;
var ScreenSignleWidth = 581;	// 定义单屏显示宽度;

function scrollit(p)
{
	if ( p.toString() == "right" && ScreenDepth <= ScreenDepthMax )
	{
		for ( i = (ScreenDepth * ScreenSignleWidth); i <= ((ScreenDepth + 1) * ScreenSignleWidth); i ++ )
		{
			i += 10;
			parent.nav.scroll(i,0)
		}
		ScreenDepth ++;
	}
	if ( p.toString() == "left" && ScreenDepth != 0 )
	{
		ScreenDepth --;
		for ( i = ((ScreenDepth + 1) * ScreenSignleWidth); i >= (ScreenDepth * ScreenSignleWidth); i -- )
		{
			i -= 10;
			parent.nav.scroll(i,0)
		}
	}
}