When i resize the sub panel of split container(programatically), there is a ugly blank(usually on the right side),
i guess it is caused by container background mob.

i searched on internet, there are a few article on this issue, but none of them give a straight solution, i don't
have time to re-create a split-container, but only derived it from System.Window.Forms.SpitterContainer.

i tried override OnPaintBackgound, SetStyle, and WM_ thing, not work.

I am now still working with .Net 2.0, don't know much about 3.0. If there a good solution to at lease reduce the flicker.
Thanks very much.

Every time i put an question on this web site, i could light my idea.
i found a simple way to solve this problem, Ahaha

First Derive Split Container and Override:
private const int WM_ERASEBKGND = 0x0014;

protected override void WndProc(ref Message msg)
{
switch (msg.Msg)
{
case WM_ERASEBKGND:
System.Diagnostics.Debug.WriteLine("Avoided clear bg");
return;
}

base.WndProc(ref msg);
}
Second:
No dock control to SplitContainer's Panel2, Resize the control manually.

I've find this accidentally, got a wonderful result, testing continue...

Every time i put an question on this web site, i could light my idea.
i found a simple way to solve this problem, Ahaha

First Derive Split Container and Override:
private const int WM_ERASEBKGND = 0x0014;

protected override void WndProc(ref Message msg)
{
switch (msg.Msg)
{
case WM_ERASEBKGND:
System.Diagnostics.Debug.WriteLine("Avoided clear bg");
return;
}

base.WndProc(ref msg);
}
Second:
No dock control to SplitContainer's Panel2, Resize the control manually.

I've find this accidentally, got a wonderful result, testing continue...

I’m glad to hear that you got it working. Thank you for sharing your experience here.

It will be very beneficial for other community members having the similar questions.