如何在不使用“文件下载”对话框的情况下使用WebBrowser控件下载文件?

时间:2019-04-03 09:20:39

标签: c# wpf webbrowser-control

在WPF项目中,我使用

webBrowser.Navigate(strUrl);

从服务器获取PNG图片。

出现以下对话框:

File Download dialog screenshot

如何无缝下载图片(没有对话框)?

1 个答案:

答案 0 :(得分:3)

您无需为此使用浏览器控件。

尝试使用DownloadFileAsync()

这是一个完全正常的示例。 (根据需要更改路径。)

    private void Button_Click(object sender, RoutedEventArgs e)
    {
        WebClient client = new WebClient();
        client.DownloadFileAsync(new Uri("https://www.example.com/filepath"), @"C:\Users\currentuser\Desktop\Test.png");
        client.DownloadFileCompleted += Client_DownloadFileCompleted;
        client.DownloadProgressChanged += Client_DownloadProgressChanged;
    }

    private void Client_DownloadProgressChanged(object sender, DownloadProgressChangedEventArgs e)
    {
        progressBar.Value = e.ProgressPercentage;
        TBStatus.Text = e.ProgressPercentage + "% " + e.BytesReceived + " of " + e.TotalBytesToReceive + " received.";
    }

    private void Client_DownloadFileCompleted(object sender, System.ComponentModel.AsyncCompletedEventArgs e)
    {
        MessageBox.Show("Download Completed");
    }

您可以使用以下默认应用打开下载的文件:

System.Diagnostics.Process.Start(@"C:\Users\currentuser\Desktop\Test.png");

编辑:

如果您的目标只是显示png,则可以将其下载到流中,然后在image control中显示。

完整的样本。

WebClient wc = new WebClient();
MemoryStream stream = new MemoryStream(wc.DownloadData("https://www.dropbox.com/s/l3maq8j3yzciedw/App%20in%205%20minutes.PNG?raw=1"));
System.Drawing.Bitmap bmp = new System.Drawing.Bitmap(stream);
bmp.Save(stream, System.Drawing.Imaging.ImageFormat.Png);
stream.Position = 0;
BitmapImage bi = new BitmapImage();
bi.BeginInit();
bi.StreamSource = stream;
bi.EndInit();
image1.Source = bi;

这是异步版本。

private void Button_Click(object sender, RoutedEventArgs e)
{
    WebClient wc = new WebClient();
    wc.DownloadDataAsync(new Uri("https://www.dropbox.com/s/l3maq8j3yzciedw/App%20in%205%20minutes.PNG?raw=1"));
    wc.DownloadDataCompleted += Wc_DownloadDataCompleted;
}

private void Wc_DownloadDataCompleted(object sender, DownloadDataCompletedEventArgs e)
{
    MemoryStream stream = new MemoryStream((byte[])e.Result);
    System.Drawing.Bitmap bmp = new System.Drawing.Bitmap(stream);
    bmp.Save(stream, System.Drawing.Imaging.ImageFormat.Png);
    stream.Position = 0;
    BitmapImage bi = new BitmapImage();
    bi.BeginInit();
    bi.StreamSource = stream;
    bi.EndInit();
    image1.Source = bi;
}