public string[] SearchForMovie(string SearchParameter)
{
WebClientX.DownloadDataCompleted += new
DownloadDataCompletedEventHandler(WebClientX_DownloadDataCompleted);
WebClientX.DownloadDataAsync(new Uri(
"http://www.imdb.com/find?s=all&q=ironman+&x=0&y=0"));
string sitesearchSource = Encoding.ASCII.GetString(Buffer);
}
void WebClientX_DownloadDataCompleted(object sender,
DownloadDataCompletedEventArgs e)
{
Buffer = e.Result;
throw new NotImplementedException();
}
I get this exception:
The matrix cannot be null. Refering to my byte[] variable Buffer.
So, I can conclude that the DownloadDataAsync isn't really downloading anything. What is causing this problem?
PS. How can I easily format my code so it appear properly indented here. Why can't I just copy past the code from Visual C# express and maintain the indentation here? Thanks! :D
The key word here is "async"; when you call DownloadDataAsync, it only starts the download; it isn't complete yet. You need to process the data in the callback (WebClientX_DownloadDataCompleted).
public string[] SearchForMovie(string SearchParameter)
{
WebClientX.DownloadDataCompleted += WebClientX_DownloadDataCompleted;
WebClientX.DownloadDataAsync(new Uri(uri));
}
void WebClientX_DownloadDataCompleted(object sender,
DownloadDataCompletedEventArgs e)
{
Buffer = e.Result;
string sitesearchSource = Encoding.ASCII.GetString(Buffer);
}
Also - don't assume ASCII; WebClientX.Encoding would be better; or just DownloadStringAsync:
static void Main()
{
var client = new WebClient();
client.DownloadStringCompleted += DownloadStringCompleted;
client.DownloadStringAsync(new Uri("http://google.com"));
Console.ReadLine();
}
static void DownloadStringCompleted(object sender,
DownloadStringCompletedEventArgs e)
{
if (e.Error == null && !e.Cancelled)
{
Console.WriteLine(e.Result);
}
}
Related
I implemented a function in a windows form application to capture and read needed tabular data from a file (sourcedata.data) and save it in another file (result.data ).
How i and by using the application can capture a real time stream data like such available here :https://data.sparkfun.com/streams in csv or .data file to use it.
Or are there any direct waya to read the stream data directly from the website source periodically ?
private void button5_Click(object sender, EventArgs e)
{
List<string[]> rows = new List<string[]>();
int[] indexes = { 0, 1, 3, 5, 6, 7, 8, 9 };
using (var reader = new StreamReader(#"sourcedata.data"))
{
using (StreamWriter writetext = new StreamWriter("result.data"))
{
while (!reader.EndOfStream)
{
var line = reader.ReadLine();
if (line.IndexOf(',') == -1)
continue;
string[] values = line.Split(',');
string[] row = new string[indexes.Length];
int insertIndex = 0;
for (int i = 0; i < values.Length; i++)
{
string val = values[i];
if (val.Trim() == "?")
goto BREAK;
if (indexes.Contains(i))
row[insertIndex++] = val;
}
rows.Add(row);
writetext.WriteLine(String.Join(",", row));
BREAK:;
}
}
}
}
You have two split your problem into two separated sub problems:
Write a method public static string DownloadData(...) which will download the data from the source. This can be done by any HTTP client or library you can find like System.Net.Http.HttpClient or System.Net.WebClient.
See How to download a file from a URL in C#?
Add/start a timer which calls this method periodically. You can use classes like System.Windows.Forms.Timer or System.Timers.Timer.
See What is the best way to implement a "timer"?
#Progman
It is the code
public partial class Download : Form
{
public Download()
{
InitializeComponent();
}
WebClient client;
private void btnDownload_Click(object sender, EventArgs e)
{
string url = txtUrl.Text;
if (!string.IsNullOrEmpty(url))
{
Thread thread = new Thread(() =>
{
Uri uri = new Uri(url);
string filename = System.IO.Path.GetFileName(uri.AbsolutePath);
client.DownloadFileAsync(uri, Application.StartupPath + "/" + filename);
});
thread.Start();
}
}
private void Download_Load(object sender, EventArgs e)
{
client = new WebClient();
client.DownloadProgressChanged += Client_DownloadProgressChanged;
client.DownloadFileCompleted += Client_DownloadFileCompleted;
}
private void Client_DownloadFileCompleted(object sender, AsyncCompletedEventArgs e)
{
MessageBox.Show("Download Completed.", "Message", MessageBoxButtons.OK, MessageBoxIcon.Information);
}
private void Client_DownloadProgressChanged(object sender, DownloadProgressChangedEventArgs e)
{
Invoke(new MethodInvoker(delegate ()
{
progressBar.Minimum = 0;
double recieve = double.Parse(e.BytesReceived.ToString());
double total = double.Parse(e.TotalBytesToReceive.ToString());
double percentage = recieve / total * 100;
lblStatus.Text = $"Download {string.Format("{0:0.##}", percentage)}%";
progressBar.Value = int.Parse(Math.Truncate(percentage).ToString());
}));
}
}
Im trying to download files using extended WebClient with set timeout and I have a problem with the timeout (or what I think should cause timeout).
When I start the download with WebClient and receive some data, then disconnect wifi - my program hangs on the download without throwing any exception. How can I fix this?
EDIT: It actually throws exception but way later than it should (5 minutes vs 1 second which i set) - that is what Im trying to fix.
If you find anything else wrong with my code, please let me know too. Thank you for help
This is my extended class
class WebClientWithTimeout : WebClient
{
protected override WebRequest GetWebRequest(Uri address)
{
WebRequest w = base.GetWebRequest(address);
w.Timeout = 1000;
return w;
}
}
This is the download
using (WebClientWithTimeout wct = new WebClientWithTimeout())
{
ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12;
try
{
wct.DownloadFile("https://example.com", file);
}
catch (Exception e)
{
Console.WriteLine("Download: {0} failed with exception:{1} {2}", file, Environment.NewLine, e);
}
}
Try this, you can avoid UI blocking by this. Coming the WiFi when device connects to WiFi the download resumes.
//declare globally
DateTime lastDownloaded = DateTime.Now;
Timer t = new Timer();
WebClient wc = new WebClient();
//declarewherever you initiate download my case button click
private void button1_Click(object sender, EventArgs e)
{
wc.DownloadProgressChanged += Wc_DownloadProgressChanged;
wc.DownloadFileCompleted += Wc_DownloadFileCompleted;
lastDownloaded = DateTime.Now;
t.Interval = 1000;
t.Tick += T_Tick;
wc.DownloadFileAsync(new Uri("https://github.com/google/google-api-dotnet-client/archive/master.zip"), #"C:\Users\chkri\AppData\Local\Temp\master.zip");
}
private void T_Tick(object sender, EventArgs e)
{
if ((DateTime.Now - lastDownloaded).TotalMilliseconds > 1000)
{
wc.CancelAsync();
}
}
private void Wc_DownloadFileCompleted(object sender, AsyncCompletedEventArgs e)
{
if (e.Error != null)
{
lblProgress.Text = e.Error.Message;
}
}
private void Wc_DownloadProgressChanged(object sender, DownloadProgressChangedEventArgs e)
{
lastDownloaded = DateTime.Now;
lblProgress.Text = e.BytesReceived + "/" + e.TotalBytesToReceive;
}
I will try my best to explain the issue clearly. I'm using the code from
http://msdn.microsoft.com/en-us/magazine/dn385710.aspx
to create a photo sharing app. I am able to FTP images to my server fine. The issue I'm facing is when I tried to create the app to preview the picture and then FTP it. The FTP will still transfer the file, but the file size is always 0 size. I'm not sure if this is a bug or possibly me not disposing a certain object before FTP. Below are my codes:
Page 1
BitmapImage bitmapImage;
public PhotoPreview()
{
InitializeComponent();
btnYes.Tap += btnYes_Tap;
imgPreview.Width = G.getScreenWidth();
imgPreview.Height = G.getScreenHeight() - 250;
//windows phone 8 bug. When bitmap image is set...it blocks the FTP process thread. Will perform FTP on seperate page
previewPhoto();
}
void previewPhoto()
{
bitmapImage = new BitmapImage();
bitmapImage.SetSource(G.myStream);
imgPreview.Source = bitmapImage;
}
private void btnYes_Tap(object sender, System.Windows.Input.GestureEventArgs e)
{
disposeImage(bitmapImage);
NavigationService.Navigate(new Uri("/PhotoFTP.xaml", UriKind.Relative));
}
private void disposeImage(BitmapImage img)
{
if (img != null)
{
try
{
using (var ms = new MemoryStream(new byte[] { 0x0 }))
{
img = new BitmapImage();
img.SetSource(ms);
}
}
catch (Exception e)
{
System.Diagnostics.Debug.WriteLine("ImageDispose FAILED " + e.Message);
}
}
}
Page 2
const string
IP_ADDRESS = "888.88.888",
FTP_USERNAME = "test",
FTP_PASSWORD = "test123"
;
string filename;
FtpClient ftpClient = null;
TestLogger logger = null;
public PhotoFTP()
{
InitializeComponent();
DateTime thisDay = DateTime.Today;
string timestamp = thisDay.Hour.ToString() + "_" + thisDay.Minute.ToString() + "_" + thisDay.Second.ToString();
filename = timestamp + ".jpg";
}
protected override void OnNavigatedTo(NavigationEventArgs e)
{
Test_connect();
}
private async void Test_connect()
{
logger = TestLogger.GetDefault(this.Dispatcher);
lstLogs.ItemsSource = logger.Logs;
ftpClient = new FtpClient(IP_ADDRESS, this.Dispatcher);
ftpClient.FtpConnected += ftpClient_FtpConnected;
ftpClient.FtpFileUploadSucceeded += ftpClient_FtpFileUploadSucceeded;
ftpClient.FtpFileUploadFailed += ftpClient_FtpFileUploadFailed;
ftpClient.FtpAuthenticationSucceeded += ftpClient_FtpAuthenticationSucceeded;
ftpClient.FtpAuthenticationFailed += ftpClient_FtpAuthenticationFailed;
logger = TestLogger.GetDefault(this.Dispatcher);
await ftpClient.ConnectAsync();
logger.AddLog("Connecting...");
}
async void ftpClient_FtpConnected(object sender, EventArgs e)
{
logger.AddLog("Preparing...");
await (sender as FtpClient).AuthenticateAsync(FTP_USERNAME, FTP_PASSWORD);
}
private async void Test_upload()
{
logger.AddLog("Uploading photo...");
await ftpClient.UploadFileAsync(G.myStream, "username_timestamp.jpg");
}
void ftpClient_FtpAuthenticationFailed(object sender, EventArgs e)
{
logger.AddLog("Connection error.");
}
void ftpClient_FtpAuthenticationSucceeded(object sender, EventArgs e)
{
logger.AddLog("Connection established.");
Test_upload();
}
void ftpClient_FtpFileUploadFailed(object sender, FtpFileTransferFailedEventArgs e)
{
logger.AddLog("Failed.");
}
Boolean firstTime = true;
void ftpClient_FtpFileUploadSucceeded(object sender, FtpFileTransferEventArgs e)
{
logger.AddLog("Completed.");
}
If I comment out the line previewPhoto(); in page 1, it will FTP the file to my server fine. I believe the issue is the
bitmapImage.SetSource(G.myStream);
I've also tried to create two separate stream. One to preview the photo and the other to FTP. The result still resulted in 0 size file when FTP to the my server.
It's because the BitmapImage reads to the end of the stream, so the FtpClient has no data to read/upload.
Use Stream.Seek to reset the stream pointer back to the beginning.
G.myStream.Seek(0, SeekOrigin.Begin);
I am trying to monitor traffic using FiddlerCore and WebBrowser Controller, I have below code to capture web requests in C#
private void button1_Click(object sender, EventArgs e)
{
List<Fiddler.Session> oAllSessions = new List<Fiddler.Session>();
URLMonInterop.SetProxyInProcess("127.0.0.1:8888", "<-loopback>");
webBrowser1.ScriptErrorsSuppressed = true;
WebProxy myProxy = new WebProxy();
Uri newUri = new Uri("http://localhost:8888");
myProxy.Address = newUri;
Fiddler.FiddlerApplication.Startup(8888, FiddlerCoreStartupFlags.Default);
Fiddler.FiddlerApplication.AfterSessionComplete += delegate(Fiddler.Session oS)
{
Monitor.Enter(oAllSessions);
oAllSessions.Add(oS);
Monitor.Exit(oAllSessions);
};
webBrowser1.Navigate("http://www.test.com/");
while (webBrowser1.ReadyState != WebBrowserReadyState.Complete)
{
System.Windows.Forms.Application.DoEvents();
}
var message = string.Join(Environment.NewLine, oAllSessions);
textBox1.Text = textBox1.Text + message;
Fiddler.FiddlerApplication.Shutdown();
}
private void Form1_FormClosing(object sender, FormClosingEventArgs e)
{
Fiddler.FiddlerApplication.Shutdown();
URLMonInterop.ResetProxyInProcessToDefault();
}
It is only returning just one request response (given url in webBroser.Navigate), I can not see requests for images, css and other loaded files on example site. I could not find any info on this, Can someone please help me to understand on how I can capture all GET POST requests when webBroswer.Navigate to given URL?
updated:
delegate void updateUI();
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
Fiddler.FiddlerApplication.AfterSessionComplete += FiddlerApplication_AfterSessionComplete;
Fiddler.FiddlerApplication.Startup(8888, FiddlerCoreStartupFlags.Default);
webBrowser1.ScriptErrorsSuppressed = true;
WebProxy myProxy = new WebProxy();
Uri newUri = new Uri("http://localhost:8888");
myProxy.Address = newUri;
string[] urls = new string[] { "http://localhost/test/page1",
"http://localhost/test/page2 "
};
foreach (string url in urls)
{
webBrowser1.Navigate(url);
// Capture root url
listBox1.Invoke(new updateUI(() =>
{
listBox1.Items.Add(url);
}));
while (webBrowser1.ReadyState != WebBrowserReadyState.Complete)
{
System.Windows.Forms.Application.DoEvents();
}
// Hack as I am not sure what to do here so wait 10 second for webBrowser to load all requests otherwise I only get last url data in listbox
for (int i = 0; i <= 10; i++)
{
System.Windows.Forms.Application.DoEvents();
Thread.Sleep(1000);
}
}
}
void FiddlerApplication_AfterSessionComplete(Session oSession)
{
var regex = new Regex("keywords-in-url-to-match");
// If my desired keyword match then grab request POST body
if (regex.IsMatch(oSession.fullUrl.ToString()))
{
string requestBody = oSession.GetRequestBodyAsString();
// Capture url and request body. This url is not root url
listBox1.Invoke(new updateUI(() =>
{
listBox1.Items.Add(oSession.fullUrl);
listBox1.Items.Add(System.Web.HttpUtility.UrlDecode(requestBody));
}));
}
}
private void Form1_FormClosing(object sender, FormClosingEventArgs e)
{
Fiddler.FiddlerApplication.Shutdown();
}
What makes you think that the other items aren't being pulled from the cache?
You shouldn't use FiddlerCoreStartupFlags.Default if you're going to use SetProxyInProcess; the former sets the proxy for every process on the system while the latter sets the proxy only for the current process.
i want to read a file by its Uri, and ask the user to store the file. This has to be done using Silverlight.
Ive tried the following, and it didnt work..
client.OpenReadCompleted += new OpenReadCompletedEventHandler(client_OpenReadCompleted);
private void Build_Log_Click(object sender, RoutedEventArgs e)
{
Uri uri = new Uri("http:***.log");
client.OpenWriteAsync(uri);
}
private void client_OpenReadCompleted(object sender, OpenReadCompletedEventArgs e)
{
bool? result = textDialog.ShowDialog();
if (result == true)
{
var text = e.Result;
System.IO.Stream fileStream = textDialog.OpenFile();
StreamWriter sw = new System.IO.StreamWriter(fileStream);
sw.Write(text);
sw.Flush();
sw.Close();
}
}
As from my comment, client.OpenWriteAsync should be client.OpenReadAsync ( yes this is a indiscriminated way of gaining some points :) )