Download file and automatically save it to folder

Question

I'm trying to make a UI for downloading files from my site. The site have zip-files and these need to be downloaded to the directory entered by the user. However, I can't succeed to download the file, it just opens up from a temporary folder.

Code:

private void webBrowser1_Navigating(object sender, WebBrowserNavigatingEventArgs e)
{
        e.Cancel = true;
        string filepath = null;
            filepath = textBox1.Text;
            WebClient client = new WebClient();
            client.DownloadFileCompleted += new AsyncCompletedEventHandler(client_DownloadFileCompleted);
            client.DownloadFileAsync(e.Url, filepath);
}

Full sourcecode: http://en.paidpaste.com/LqEmiQ

Answer 1

If you don't want to use "WebClient" or/and need to use the System.Windows.Forms.WebBrowser e.g. because you want simulate a login first, you can use this extended WebBrowser which hooks the "URLDownloadToFile" Method from the Windows URLMON Lib and uses the Context of the WebBrowser

Infos: http://www.pinvoke.net/default.aspx/urlmon/URLDownloadToFile%20.html

using System;
using System.IO;
using System.Runtime.InteropServices;
using System.Windows.Forms;

namespace dataCoreLib.Net.Webpage
{
        public class WebBrowserWithDownloadAbility : WebBrowser
        {
            /// <summary>
            /// The URLMON library contains this function, URLDownloadToFile, which is a way
            /// to download files without user prompts.  The ExecWB( _SAVEAS ) function always
            /// prompts the user, even if _DONTPROMPTUSER parameter is specified, for "internet
            /// security reasons".  This function gets around those reasons.
            /// </summary>
            /// <param name="callerPointer">Pointer to caller object (AX).</param>
            /// <param name="url">String of the URL.</param>
            /// <param name="filePathWithName">String of the destination filename/path.</param>
            /// <param name="reserved">[reserved].</param>
            /// <param name="callBack">A callback function to monitor progress or abort.</param>
            /// <returns>0 for okay.</returns>
            /// source: http://www.pinvoke.net/default.aspx/urlmon/URLDownloadToFile%20.html
            [DllImport("urlmon.dll", CharSet = CharSet.Auto, SetLastError = true)]
            static extern Int32 URLDownloadToFile(
                [MarshalAs(UnmanagedType.IUnknown)] object callerPointer,
                [MarshalAs(UnmanagedType.LPWStr)] string url,
                [MarshalAs(UnmanagedType.LPWStr)] string filePathWithName,
                Int32 reserved,
                IntPtr callBack);


            /// <summary>
            /// Download a file from the webpage and save it to the destination without promting the user
            /// </summary>
            /// <param name="url">the url with the file</param>
            /// <param name="destinationFullPathWithName">the absolut full path with the filename as destination</param>
            /// <returns></returns>
            public FileInfo DownloadFile(string url, string destinationFullPathWithName)
            {
                URLDownloadToFile(null, url, destinationFullPathWithName, 0, IntPtr.Zero);
                return new FileInfo(destinationFullPathWithName);
            }
        }
    }