웹 사이트에서 C #으로 파일을 다운로드하는 방법

웹 사이트에서 C #으로 파일을 다운로드하는 방법

---

웹 사이트에서 Windows 응용 프로그램 형식으로 파일을 다운로드하여 특정 디렉토리에 넣을 수 있습니까?

---

와 웹 클라이언트 클래스 :

using System.Net;
//...
WebClient Client = new WebClient ();
Client.DownloadFile("http://i.stackoverflow.com/Content/Img/stackoverflow-logo-250.png", @"C:\folder\stackoverflowlogo.png");

---

사용 WebClient.DownloadFile:

using (WebClient client = new WebClient())
{
    client.DownloadFile("http://csharpindepth.com/Reviews.aspx", 
                        @"c:\Users\Jon\Test\foo.txt");
}

---

요청을하기 전에 파일 다운로드 중에 상태를 알고 있거나 자격 증명을 사용해야 할 수 있습니다.

다음은 이러한 옵션을 다루는 예입니다.

Uri ur = new Uri("http://remotehost.do/images/img.jpg");

using (WebClient client = new WebClient()) {
    //client.Credentials = new NetworkCredential("username", "password");
    String credentials = Convert.ToBase64String(Encoding.ASCII.GetBytes("Username" + ":" + "MyNewPassword"));
    client.Headers[HttpRequestHeader.Authorization] = $"Basic {credentials}";

    client.DownloadProgressChanged += WebClientDownloadProgressChanged;
    client.DownloadDataCompleted += WebClientDownloadCompleted;
    client.DownloadFileAsync(ur, @"C:\path\newImage.jpg");
}

그리고 콜백의 기능은 다음과 같이 구현됩니다.

void WebClientDownloadProgressChanged(object sender, DownloadProgressChangedEventArgs e)
{
    Console.WriteLine("Download status: {0}%.", e.ProgressPercentage);

    // updating the UI
    Dispatcher.Invoke(() => {
        progressBar.Value = e.ProgressPercentage;
    });
}

void WebClientDownloadCompleted(object sender, DownloadDataCompletedEventArgs e)
{
    Console.WriteLine("Download finished!");
}

(Ver 2)-Lambda 표기법 : 이벤트 처리를위한 다른 가능한 옵션

client.DownloadProgressChanged += new DownloadProgressChangedEventHandler(delegate(object sender, DownloadProgressChangedEventArgs e) {
    Console.WriteLine("Download status: {0}%.", e.ProgressPercentage);

    // updating the UI
    Dispatcher.Invoke(() => {
        progressBar.Value = e.ProgressPercentage;
    });
});

client.DownloadDataCompleted += new DownloadDataCompletedEventHandler(delegate(object sender, DownloadDataCompletedEventArgs e){
    Console.WriteLine("Download finished!");
});

(Ver 3)-우리는 더 잘할 수 있습니다

client.DownloadProgressChanged += (object sender, DownloadProgressChangedEventArgs e) =>
{
    Console.WriteLine("Download status: {0}%.", e.ProgressPercentage);

    // updating the UI
    Dispatcher.Invoke(() => {
        progressBar.Value = e.ProgressPercentage;
    });
};

client.DownloadDataCompleted += (object sender, DownloadDataCompletedEventArgs e) => 
{
    Console.WriteLine("Download finished!");
};

(Ver 4)-또는

client.DownloadProgressChanged += (o, e) =>
{
    Console.WriteLine($"Download status: {e.ProgressPercentage}%.");

    // updating the UI
    Dispatcher.Invoke(() => {
        progressBar.Value = e.ProgressPercentage;
    });
};

client.DownloadDataCompleted += (o, e) => 
{
    Console.WriteLine("Download finished!");
};

---

물론 HttpWebRequest입니다..

HttpWebRequest설정 이 완료되면 응답 스트림을 파일 StreamWriter( BinaryWriter또는 TextWriterMIME 유형에 따라)에 저장할 수 있으며 하드 드라이브에 파일이 있습니다.

EDIT: Forgot about WebClient. That works good unless as long as you only need to use GET to retrieve your file. If the site requires you to POST information to it, you'll have to use a HttpWebRequest, so I'm leaving my answer up.

---

You can use this code to Download file from a WebSite to Desktop:

using System.Net;

WebClient Client = new WebClient ();
client.DownloadFileAsync(new Uri("http://www.Address.com/File.zip"), Environment.GetFolderPath(Environment.SpecialFolder.Desktop) + "File.zip");

---

Try this example:

public void TheDownload(string path)
{
  System.IO.FileInfo toDownload = new System.IO.FileInfo(HttpContext.Current.Server.MapPath(path));

  HttpContext.Current.Response.Clear();
  HttpContext.Current.Response.AddHeader("Content-Disposition",
             "attachment; filename=" + toDownload.Name);
  HttpContext.Current.Response.AddHeader("Content-Length",
             toDownload.Length.ToString());
  HttpContext.Current.Response.ContentType = "application/octet-stream";
  HttpContext.Current.Response.WriteFile(patch);
  HttpContext.Current.Response.End();
} 

The implementation is done in the follows:

TheDownload("@"c:\Temporal\Test.txt"");

Source: http://www.systemdeveloper.info/2014/03/force-downloading-file-from-c.html

---

Also you can use DownloadFileAsync method in WebClient class. It downloads to a local file the resource with the specified URI. Also this method does not block the calling thread.

Sample:

    webClient.DownloadFileAsync(new Uri("http://www.example.com/file/test.jpg"), "test.jpg");

For more information:

http://csharpexamples.com/download-files-synchronous-asynchronous-url-c/

참고URL : https://stackoverflow.com/questions/525364/how-to-download-a-file-from-a-website-in-c-sharp