C# 无边框窗体边框阴影效果

通过下面代码在构造函数中调用方法 SetShadow();

即可实现无边框窗体的阴影效果了

需要添加命名空间 using System.Runtime.InteropServices;

        private const int CS_DropSHADOW = 0x20000;
        private 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);    
        
        private void SetShadow()
        {
            SetClassLong(this.Handle, GCL_STYLE, GetClassLong(this.Handle, GCL_STYLE) | CS_DropSHADOW); 
        }    

这边这给出一个写好的Form的基类，功能Form阴影和Form的移动功能。怎么用应该都知道吧...

把自己的Form继承该BaseForm即可实现功能

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Drawing;
using System.Runtime.InteropServices;

namespace MQXS
{
    public class BaseForm:Form
    {
        public BaseForm()
        {
            Initialize();
        }
        /// <summary>
        /// 
        /// </summary>
        /// <param name="e"></param>
        protected override void OnMouseDown(MouseEventArgs e)
        {
            base.OnMouseDown(e);
            _IsMouseDown = true;
            _startPoint = Control.MousePosition;
            _oldLocation = this.Location;
        }
        /// <summary>
        /// 
        /// </summary>
        /// <param name="e"></param>
        protected override void OnMouseMove(MouseEventArgs e)
        {
            base.OnMouseMove(e);
            if (!_IsMouseDown) return;
            Point p=Control.MousePosition;
            this.Location = new Point(p.X - _startPoint.X + _oldLocation.X, p.Y - _startPoint.Y + _oldLocation.Y);
        }
        /// <summary>
        /// 
        /// </summary>
        /// <param name="e"></param>
        protected override void OnMouseUp(MouseEventArgs e)
        {
            base.OnMouseUp(e);
            _IsMouseDown = false;
        }
        /// <summary>
        /// 
        /// </summary>
        private void Initialize()
        {
            this.FormBorderStyle = System.Windows.Forms.FormBorderStyle.None;
            this.StartPosition = FormStartPosition.CenterScreen;
            this.SetStyle(ControlStyles.AllPaintingInWmPaint | ControlStyles.OptimizedDoubleBuffer, true);
            SetClassLong(this.Handle, GCL_STYLE, GetClassLong(this.Handle, GCL_STYLE) | CS_DropSHADOW); //API函数加载，实现窗体边框阴影效果
        }

        private Point _oldLocation;
        private Point _startPoint;
        private bool _IsMouseDown;

        #region 窗体边框阴影效果变量申明

        private const int CS_DropSHADOW = 0x20000;
        private const int GCL_STYLE = (-26);
        //声明Win32 API
        [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);

        #endregion
    }
}

效果图：

源码下载

模拟API自绘阴影源码下载 如上图