c#无边框窗口初步美化

给无边框窗口添加可拖动和阴影

首先添加引用

using System.Runtime.InteropServices;

再添加所需常量

		//窗体阴影常量
        public const int CS_DropSHADOW = 0x20000;
        public const int GCL_STYLE = (-26);
        [DllImport("user32.dll", CharSet = CharSet.Auto)]
        public static extern int SetClassLong(IntPtr hwnd, int nIndex, int dwNewLong);
        [DllImport("user32.dll", CharSet = CharSet.Auto)]
        public static extern int GetClassLong(IntPtr hwnd, int nIndex);
        //窗体拖动常量
        [DllImport("user32.dll")]//拖动无窗体的控件
        public static extern bool ReleaseCapture();
        [DllImport("user32.dll")]
        public static extern bool SendMessage(IntPtr hwnd, int wMsg, int wParam, int lParam);
        public const int WM_SYSCOMMAND = 0x0112;
        public const int SC_MOVE = 0xF010;
        public const int HTCAPTION = 0x0002;

根据所需常量在窗口构造方法里调用执行

DAL.SetClassLong(this.Handle, DAL.GCL_STYLE, DAL.GetClassLong(this.Handle, DAL.GCL_STYLE) | DAL.CS_DropSHADOW);

效果

参考：
https://blog.youkuaiyun.com/qq_36819953/article/details/82775766
https://blog.youkuaiyun.com/C_S_D_N_USER/article/details/45111969