C# 大于屏幕的窗体

1.使用SetWindowPos就可以做到这一点，只是最后一个参数要选对。

RECT windowRect = new RECT();
User32.GetWindowRect(MyForm2.Handle, ref windowRect);
User32.SetWindowPos(MyForm2.Handle, 0, 0, 0, 5000, 500, ApiConstants.SWP_NOSENDCHANGING);

2.虽然设置完后窗体的大小改变了，但如果窗体的一旦重绘又会被屏幕大小限制而缩小。所以看下面的代码：

protected override void WndProc(ref Message m)
        {
            const int WM_GETMINMAXINFO = 0x24;
            if (m.Msg == WM_GETMINMAXINFO)
            {
                MINMAXINFO mmi = (MINMAXINFO)m.GetLParam(typeof(MINMAXINFO));
                mmi.ptMinTrackSize.x = this.Size.Width;
                mmi.ptMinTrackSize.y = this.Size.Height;
                Marshal.StructureToPtr(mmi, m.LParam, true);
            }
            base.WndProc(ref m);
        }

[StructLayout(LayoutKind.Sequential)]
    public struct RECT
    {
        public int left;
        public int top;
        public int right;
        public int bottom;
    }

    public struct POINTAPI 
    { 
        public int x; 
        public int y;        
    }

    public struct MINMAXINFO 
    { 
        public POINTAPI ptReserved; 
        public POINTAPI ptMaxSize; 
        public POINTAPI ptMaxPosition; 
        public POINTAPI ptMinTrackSize; 
        public POINTAPI ptMaxTrackSize;        
    }

以上代码在VS2010+Windows7Ultimate下调试通过，运行达到效果。