LeCall/Lecall/DownloadHand...

using CefSharp;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace Lecall
{
    internal class DownloadHandler : IDownloadHandler
    {
        //public event EventHandler<DownloadItem> OnBeforeDownloadFired;

        //public event EventHandler<DownloadItem> OnDownloadUpdatedFired;

        public void OnBeforeDownload(IBrowser browser, DownloadItem downloadItem, IBeforeDownloadCallback callback)
        {
            //var handler = OnBeforeDownloadFired;
            //if (handler != null)
            //{
            //    handler(this, downloadItem);
            //}

            if (!callback.IsDisposed)
            {
                using (callback)
                {
                    //callback.Continue(downloadItem.Url+ downloadItem.SuggestedFileName, true);
                    //callback.Continue(downloadItem.SuggestedFileName, true );
                    FrmDownLoad myfrm = new FrmDownLoad();
                    myfrm.originalurl  = downloadItem.Url;
                    myfrm.filename = downloadItem.SuggestedFileName;
                    myfrm.Show();
                    //DownloadFile(downloadItem.OriginalUrl, @"C:\123.rar");
                }
            }
        }

        public bool OnDownloadUpdated(IBrowser browser, DownloadItem downloadItem, IDownloadItemCallback callback)
        {
            return false;
            //var handler = OnDownloadUpdatedFired;
            //if (handler != null)
            //{
            //    handler(this, downloadItem);
            //}

        }

        public void  OnDownloadUpdated(IWebBrowser browserControl, IBrowser browser, DownloadItem downloadItem, IDownloadItemCallback callback)
        {
            
            //var handler = OnDownloadUpdatedFired;
            //if (handler != null)
            //{
            //    handler(this, downloadItem);
            //}

        }

        public void OnBeforeDownload(IWebBrowser browserControl, IBrowser browser, DownloadItem downloadItem, IBeforeDownloadCallback callback)
        {
            //var handler = OnDownloadUpdatedFired;
            //if (handler != null)
            //{
            //    handler(this, downloadItem);
            //}
            if (!callback.IsDisposed)
            {
                using (callback)
                {
                    //callback.Continue(downloadItem.Url+ downloadItem.SuggestedFileName, true);
                    //callback.Continue(downloadItem.SuggestedFileName, true );
                    FrmDownLoad myfrm = new FrmDownLoad();
                    myfrm.originalurl = downloadItem.Url;
                    myfrm.filename = downloadItem.SuggestedFileName;
                    myfrm.Show();
                    //DownloadFile(downloadItem.OriginalUrl, @"C:\123.rar");
                }
            }
        }


        /// <summary>        
        /// c#,.net 下载文件        
        /// </summary>        
        /// <param name="URL">下载文件地址</param>       
        /// 
        /// <param name="Filename">下载后的存放地址</param>        
        /// <param name="Prog">用于显示的进度条</param>        
        /// 
        public void DownloadFile(string URL, string filename)
        {
            float percent = 0;
            try
            {
                System.Net.HttpWebRequest Myrq = (System.Net.HttpWebRequest)System.Net.HttpWebRequest.Create(URL);
                System.Net.HttpWebResponse myrp = (System.Net.HttpWebResponse)Myrq.GetResponse();
                long totalBytes = myrp.ContentLength;
                #region 保存文件对话框
                SaveFileDialog saveFileDialog1 = new SaveFileDialog();

                //设置文件类型  
                saveFileDialog1.Filter = " xls files(*.xls)|*.txt|All files(*.*)|*.*";
                //设置文件名称：
                saveFileDialog1.FileName = filename;

                //设置默认文件类型显示顺序  
                saveFileDialog1.FilterIndex = 2;

                //保存对话框是否记忆上次打开的目录  
                saveFileDialog1.RestoreDirectory = true;

                //点了保存按钮进入  
                if (saveFileDialog1.ShowDialog() == DialogResult.OK)
                {

                }
                else
                { return; }
                    #endregion
                    System.IO.Stream st = myrp.GetResponseStream();
                System.IO.Stream so = new System.IO.FileStream(filename, System.IO.FileMode.Create);
                long totalDownloadedByte = 0;
                byte[] by = new byte[1024];
                int osize = st.Read(by, 0, (int)by.Length);
                while (osize > 0)
                {
                    totalDownloadedByte = osize + totalDownloadedByte;
                    System.Windows.Forms.Application.DoEvents();
                    so.Write(by, 0, osize);

                    osize = st.Read(by, 0, (int)by.Length);

                    percent = (float)totalDownloadedByte / (float)totalBytes * 100;

                    System.Windows.Forms.Application.DoEvents(); //必须加注这句代码，否则label1将因为循环执行太快而来不及显示信息
                }
                so.Close();
                st.Close();
            }
            catch (System.Exception)
            {
                throw;
            }
        }
    }
}