C#: WebRequest和WebResponse下载文件示例

Bertha 。 2022-08-05 05:27 289阅读 0赞

using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Windows; using System.Windows.Controls; using System.Windows.Data; using System.Windows.Documents; using System.Windows.Input; using System.Windows.Media; using System.Windows.Media.Imaging; using System.Windows.Navigation; using System.Windows.Shapes; using System.Net; using System.IO; using Microsoft.Win32; namespace FtpClient \{ /// <summary> /// Interaction logic for Window1.xaml /// </summary> public partial class FtpClientwindow : Window \{ private string serverDirectory; public FtpClientwindow() \{ InitializeComponent(); \} private void FillDirectoryList(Stream stream) \{ StreamReader reader = new StreamReader(stream); string content = reader.ReadToEnd(); string\[\] files = content.Split('/n'); listBoxFiles.DataContext = files; reader.Close(); \} private void buttonOpen\_Click(object sender, RoutedEventArgs e) \{ Cursor currentCusor = this.Cursor; FtpWebResponse response = null; Stream stream = null; try \{ this.Cursor = Cursors.Wait; FtpWebRequest request = (FtpWebRequest)WebRequest.Create(textBoxServer.Text); request.Credentials = new NetworkCredential(textBoxUserName.Text, passwordBox.Password); request.Method = WebRequestMethods.Ftp.ListDirectory; response = (FtpWebResponse)request.GetResponse(); stream = response.GetResponseStream(); FillDirectoryList(stream); serverDirectory = null; buttonOpenDirectory.IsEnabled = false; buttonGetFile.IsEnabled = false; \} catch (WebException ex) \{ MessageBox.Show(ex.Message, "Error FTP Client", MessageBoxButton.OK, MessageBoxImage.Error); \} catch(IOException ex) \{ MessageBox.Show(ex.Message, "Error FTP Client", MessageBoxButton.OK, MessageBoxImage.Error); \} finally \{ if (response != null) \{ response.Close(); \} if (stream != null) \{ stream.Close(); \} this.Cursor = currentCusor; \} \} private void buttonOpenDirectory\_Click(object sender, RoutedEventArgs e) \{ Cursor currentCursor = this.Cursor; FtpWebResponse response = null; Stream stream = null; try \{ this.Cursor = Cursors.Wait; string subDirectory = listBoxFiles.SelectedValue.ToString().Trim(); if (serverDirectory != null) \{ serverDirectory += @"/" + subDirectory; \} else \{ serverDirectory = subDirectory; \} Uri baseUri = new Uri(textBoxServer.Text); Uri uri = new Uri(baseUri, serverDirectory); FtpWebRequest request = (FtpWebRequest)WebRequest.Create(uri); request.Credentials = new NetworkCredential(textBoxUserName.Text, passwordBox.Password); request.Method = WebRequestMethods.Ftp.ListDirectory; response = (FtpWebResponse)request.GetResponse(); stream = response.GetResponseStream(); FillDirectoryList(stream); \} catch (Exception ex) \{ MessageBox.Show(ex.Message, "Error FTP Client", MessageBoxButton.OK, MessageBoxImage.Error); \} finally \{ if (response != null) \{ response.Close(); \} if (stream != null) \{ stream.Close(); \} this.Cursor = currentCursor; \} \} private void buttonGetFile\_Click(object sender, RoutedEventArgs e) \{ Cursor currentCursor = this.Cursor; FtpWebResponse response = null; Stream inStream = null; Stream outStream = null; try \{ this.Cursor = Cursors.Wait; string filename = listBoxFiles.SelectedValue.ToString().Trim(); string fullFilename = serverDirectory + @"/" + filename; Uri baseUri = new Uri(textBoxServer.Text); Uri uri = new Uri(baseUri, fullFilename); FtpWebRequest request = (FtpWebRequest)WebRequest.Create(uri); request.Credentials = new NetworkCredential(textBoxUserName.Text, passwordBox.Password); request.Method = WebRequestMethods.Ftp.DownloadFile; request.UseBinary = checkBoxBinary.IsChecked??false; response = (FtpWebResponse)request.GetResponse(); inStream = response.GetResponseStream(); SaveFileDialog saveFileDialog = new SaveFileDialog(); if (saveFileDialog.ShowDialog() == true) \{ outStream = File.OpenWrite(saveFileDialog.FileName); byte\[\] buffer = new byte\[8192\]; int size = 0; while ((size = inStream.Read(buffer, 0, 8192)) > 0) \{ outStream.Write(buffer, 0, size); \} \} \} catch (WebException ex) \{ MessageBox.Show(ex.Message, "Error FTP Client", MessageBoxButton.OK, MessageBoxImage.Error); \} finally \{ if (inStream != null) \{ inStream.Close(); \} if (outStream != null) \{ outStream.Close(); \} if (response != null) \{ response.Close(); \} this.Cursor = currentCursor; \} \} private void listBoxFiles\_SelectionChanged(object sender, SelectionChangedEventArgs e) \{ buttonGetFile.IsEnabled = true; buttonOpenDirectory.IsEnabled = true; \} \} \}

![1633907056006871250.jpg][]

[1633907056006871250.jpg]: /images/20220805/dd7b1110491a4a95a44abf21786a17a9.png