Question

我尝试使用System.Windows.Forms.WebBrowser或System.Windows.Controls.WebBrowser限制文件一次下载文件。我尝试在System.Windows.Forms.WebBrowser.FileDowload事件中捕获此信息，但无法知道文件何时完全下载。有没有什么办法可以在Windows.Forms.WebBrowser或Windows.Controls.WebBrowser完成文件下载的时间。感谢。

    void descargaCompleta(object sender, WebBrowserDocumentCompletedEventArgs e)
    {
        // When the download is complete
        descargando = false;
    }

    void solo1Descarga (object sender, System.EventArgs e)
    {
        System.Windows.Forms.WebBrowser web = (System.Windows.Forms.WebBrowser)sender;

        // Ask for Mutex
        descargas.WaitOne();

        descargando = true;

        while (descargando)
            ;

        descargas.ReleaseMutex();
    }

    // Función que Modifica la GUI
    private void UpadteTabs()
    {
        WindowsFormsHost contWeb = new WindowsFormsHost();
        System.Windows.Forms.WebBrowser nav = new System.Windows.Forms.WebBrowser();
        // I set the Events to WebBrowser
        nav.FileDownload += new EventHandler (solo1Descarga);
        nav.DocumentCompleted += new WebBrowserDocumentCompletedEventHandler (descargaCompleta);
    }

注意：＆＃34;一次下载文件＆＃34;表示下载单个可以同时进行。例如，如果您尝试下载大型文件和图像，则其中一个文件需要等待另一个文件

Answer 1

您可以使用WebReponse下载文件

WebRequest request = WebRequest.Create(fileUri);
WebResponse response = request.GetResponse();
DownLoadFile(response, response.ContentLength);

private void DownLoadFile(HttpWebResponse response, long contentLength)
{
    var respContentType = response.ContentType.ToUpper();
    using (var fileStream = File.OpenWrite(fileName))
    {
        using (var responseStream = response.GetResponseStream())
        {
            var buffer = new byte[1024];

            int bytesRead;
            int offset = 0;

            //Thread.Sleep(100);
            while ((bytesRead = responseStream.Read(buffer, 0, buffer.Length)) != 0)
            {
                fileStream.Write(buffer, 0, bytesRead);
                offset += bytesRead;
            }

            if (offset != response.ContentLength)
            {
                //return string.Format("Only downloaded {0} of {1} bytes", offset, response.ContentLength));
                throw new ApplicationException(string.Format("Only downloaded {0} of {1} bytes",
                                                    offset, response.ContentLength));
            }
        }
    }
}

Alternativly写一个while循环来读取二进制数据

public void DownloadFile(Uri uri, string filePathToSave)
{   
    var downloadedData = webClient.DownloadData(uri);
    while (downloadedData.Length == 0)
    {
        Thread.Sleep(2000);
        downloadedData = webClient.DownloadData(uri);
    }
    Stream file = File.Open(filePathToSave, FileMode.Create);
    file.Write(downloadedData, 0, downloadedData.Length);
    file.Close();
}

如何使用WebBrowser限制文件下载？

1 个答案: