记录

protected override void OnHandleCreated(EventArgs e)
{
InitializeStyles(); 
base.OnHandleCreated(e);
haveHandle = true;
}
private void InitializeStyles()
{
SetStyle(ControlStyles.AllPaintingInWmPaint, true);
SetStyle(ControlStyles.UserPaint, true);
UpdateStyles();
}

protected override CreateParams CreateParams
{
get
{
CreateParams cParms = base.CreateParams;
cParms.ExStyle |= 0x00080000; // WS_EX_LAYERED
return cParms;
}
}