Native.SCROLLINFO GetScrollInfo(Native.SB sb)
{
Native.SCROLLINFO si = new Native.SCROLLINFO();
si.cbSize = Marshal.SizeOf(typeof(Native.SCROLLINFO));
si.fMask = Native.SIF.ALL;
Native.GetScrollInfo(new HandleRef(this, base.Handle), sb, ref si);
return(si);
}
WmScrollResult DoWmScroll(ref System.Windows.Forms.Message m,
int num, int maximum, Native.SB bar)
{
var ret = new WmScrollResult();
if (m.LParam != IntPtr.Zero)
{
ret.absoluteScrollPos = num;
base.WndProc(ref m);
return(ret);
}
else
{
int smallChange = 50;
int largeChange = 200;
ret.isScrollEvent = true;
Native.SB sbEvt = (Native.SB)Native.LOWORD(m.WParam);
switch (sbEvt)
{
case Native.SB.LINEUP:
num += (ret.delta = -smallChange);
if (num <= 0)
{
num = 0;
}
break;
case Native.SB.LINEDOWN:
num += (ret.delta = smallChange);
if (num >= maximum)
{
num = maximum;
}
break;
case Native.SB.PAGEUP:
num += (ret.delta = -largeChange);
if (num <= 0)
{
num = 0;
}
break;
case Native.SB.PAGEDOWN:
num += (ret.delta = largeChange);
if (num >= maximum)
{
num = maximum;
}
break;
case Native.SB.THUMBTRACK:
num = this.GetScrollInfo(bar).nTrackPos;
ret.isRealtimeScroll = true;
break;
case Native.SB.THUMBPOSITION:
num = this.GetScrollInfo(bar).nTrackPos;
break;
case Native.SB.TOP:
num = 0;
break;
case Native.SB.BOTTOM:
num = maximum;
break;
case Native.SB.ENDSCROLL:
scrollBarsInfo.userIsScrolling = false;
ret.isScrollEvent = false;
break;
}
ret.absoluteScrollPos = num;
return(ret);
}
}