C#实现winform仿div+css半透明遮罩效果

本文实现在winform项目实现网页div+css关透明效果，挺帅的，在网页中要实现div的半透明遮罩层效果不难，在winform项目就不是这么容易了，下面我们来看下效果图先：   正常时：

文章来自学IT网：http://www.xueit.com/html/2010-01-08/21-1076980691437.html

下面我们来实现上图的效果控件源码：

?

using System;

using System.Collections.Generic;

using System.Text;

using System.Drawing;

using System.Windows.Forms;

using System.ComponentModel;

 

namespace MyOpaqueLayer

{

 

    [ToolboxBitmap(typeof(MyOpaqueLayer))]

    public class MyOpaqueLayer : System.Windows.Forms.Control

    {

        private bool _transparentBG = true;

        private int _alpha = 125;

 

 

        private System.ComponentModel.Container components = new System.ComponentModel.Container();

 

 

        public MyOpaqueLayer()

            : this(125, true)

        {

 

        }

 

 

        public MyOpaqueLayer(int Alpha, bool showLoadingImage)

        {

            SetStyle(System.Windows.Forms.ControlStyles.Opaque, true);

            base.CreateControl();

            this._alpha = Alpha;

            ;

            if (showLoadingImage)

            {

                PictureBox pictureBox_Loading = new PictureBox();

                pictureBox_Loading.BackColor = System.Drawing.Color.White;

                pictureBox_Loading.Image = global::MyOpaqueLayer.Properties.Resources.loading;

                pictureBox_Loading.Name = "pictureBox_Loading";

                pictureBox_Loading.Size = new System.Drawing.Size(48, 48);

                pictureBox_Loading.SizeMode = System.Windows.Forms.PictureBoxSizeMode.AutoSize;

                Point Location = new Point(this.Location.X   (this.Width - pictureBox_Loading.Width) / 2, this.Location.Y   (this.Height - pictureBox_Loading.Height) / 2);

                pictureBox_Loading.Location = Location;

                pictureBox_Loading.Anchor = AnchorStyles.None;

                this.Controls.Add(pictureBox_Loading);

            }

        }

 

 

        protected override void Dispose(bool disposing)

        {

            if (disposing)

            {

                if (!((components == null)))

                {

                    components.Dispose();

                }

            }

            base.Dispose(disposing);

        }

 

        /// <summary>

        /// 自定义绘制窗体

        /// </summary>

        /// <param name="e"></param>

        protected override void OnPaint(System.Windows.Forms.PaintEventArgs e)

        {

            float vlblControlWidth;

            float vlblControlHeight;

 

            Pen labelBorderPen;

            SolidBrush labelBackColorBrush;

 

            if (_transparentBG)

            {

                Color drawColor = Color.FromArgb(this._alpha, this.BackColor);

                labelBorderPen = new Pen(drawColor, 0);

                labelBackColorBrush = new SolidBrush(drawColor);

            }

            else

            {

                labelBorderPen = new Pen(this.BackColor, 0);

                labelBackColorBrush = new SolidBrush(this.BackColor);

            }

            base.OnPaint(e);

            vlblControlWidth = this.Size.Width;

            vlblControlHeight = this.Size.Height;

            e.Graphics.DrawRectangle(labelBorderPen, 0, 0, vlblControlWidth, vlblControlHeight);

            e.Graphics.FillRectangle(labelBackColorBrush, 0, 0, vlblControlWidth, vlblControlHeight);

 

        }

        /// <summary>

        ///

        /// </summary>

        protected override CreateParams CreateParams//v1.10

        {

            get

            {

                CreateParams cp = base.CreateParams;

                cp.ExStyle |= 0x20;  // 开启 WS_EX_TRANSPARENT,使控件支持透明

                return cp;

            }

        }

 

        [Category("myOpaqueLayer"), Description("是否使用透明,默认为True")]

        public bool TransparentBG

        {

            get { return _transparentBG; }

            set

            {

                _transparentBG = value;

                this.Invalidate();

            }

        }

 

        [Category("myOpaqueLayer"), Description("设置透明度")]

        public int Alpha

        {

            get { return _alpha; }

            set

            {

                _alpha = value;

                this.Invalidate();

            }

        }

    }

}

文章来自学IT网：http://www.xueit.com/html/2010-01-08/21-1076980691437.html

　　下载：https://files.cnblogs.com/xiaofengfeng/MyOpaqueLayer1.rar