i have a application thats writen with the pylons framework. Now i want to call some controllers from a vb.net application. How should i do this?
I've tried it like this:
Dim webclient As New WebClient
Dim dataStream As IO.Stream = webclient.OpenRead("http://192.168.0.20:5000/controller/default")
Dim reader As New StreamReader(dataStream)
Dim responseFromServer As String = reader.ReadToEnd()
Dim erg As String = responseFromServer.ToString
reader.Close()
dataStream.Close()
But instead of an json object that is generate by the pylons controller, i'll get the html code for the page which is reachable under "http://192.168.0.20:5000"
Any help would be great!
Cheers,
Nico
You're probably requesting either the wrong content type or the wrong URL.
Make sure the URL is correct, or try this code:
Dim webclient As New WebClient
webclient.Headers.Add(HttpRequestHeader.ContentType, "test/json")
Dim erg As String = webclient.DownloadString("http://192.168.0.20:5000/controller/default")
As I demonstrated, you should use the DownloadString method instead of manually using a StreamReader.
Thank you for the answer, but this brings me the same result.
I figured out that you have to first login to the page. That means i have to call another controller, which is responsible for the login. For that i have to add params in the post.
How i do this in vb.net?
Cheers Nico
Related
i want to using webrequest codes then adding google search result URL's listbox1. But i can't codes gives error.
Try
Dim adres As String = "https://www.google.com/search?q=" + TextBox1.Text
Dim istek As WebRequest = HttpWebRequest.Create(adres)
Dim cevap As WebResponse
cevap = istek.GetResponse()
Dim donenBilgiler As StreamReader = New StreamReader(cevap.GetResponseStream())
Dim gelen As String = donenBilgiler.ReadToEnd()
Dim titleIndexBaslangici As Integer = gelen.IndexOf("<link href") + 2
Dim titleIndexBitisi As Integer = gelen.Substring(titleIndexBaslangici).IndexOf(">")
ListBox1.Items.Add(gelen.Substring(titleIndexBaslangici, titleIndexBitisi))
Catch ex As Exception
MsgBox(ex.Message)
End Try
First, are you familliar with API, because that's what you need ! You might work this out with the way you want to make it but its really bad and no one will recommend you to continue like this!
What you need to look for is API, (google search API)! API "only" purpose is to access to some data (in database) with easy Http route (well documented), try it out!
If you keep trying to do it in your own way, the best result that you will get is a really bad html page that you will need to parse and you don't want that !
I'm creating a file on the fly on a WebAPI call, and sending that file back to the client.
I think I'm misunderstanding flush/close on a FileStream:
Dim path As String = tempFolder & "\" & fileName
Dim result As New HttpResponseMessage(HttpStatusCode.OK)
Dim stream As New FileStream(path, FileMode.Open)
With result
.Content = New StreamContent(stream)
.Content.Headers.ContentDisposition = New Headers.ContentDispositionHeaderValue("attachment")
.Content.Headers.ContentDisposition.FileName = fileName
.Content.Headers.ContentType = New Headers.MediaTypeHeaderValue("application/octet-stream")
.Content.Headers.ContentLength = stream.Length
End With
'stream.Flush()
'stream.Close()
'Directory.Delete(tempFolder, True)
Return result
You can see where I've commented things out above.
Questions:
Does the stream flush/close itself?
How can I delete the tempFolder after returning the result?
On top of all this, it would be great to know how to generate the file and send it to the user without writing it to the file system first. I'm confident this is possible, but I'm not sure how. I'd love to be able to understand how to do this, and solve my current problem.
Update:
I went ahead with accepted answer, and found it to be quite simple:
Dim ReturnStream As MemoryStream = New MemoryStream()
Dim WriteStream As StreamWriter = New StreamWriter(ReturnStream)
With WriteStream
.WriteLine("...")
End With
WriteStream.Flush()
WriteStream.Close()
Dim byteArray As Byte() = ReturnStream.ToArray()
ReturnStream.Flush()
ReturnStream.Close()
Then I was able to stream the content as bytearraycontent:
With result
.Content = New ByteArrayContent(byteArray)
...
End With
On top of all this, it would be great to know how to generate the file and send it to the user without writing it to the file system first. I'm confident this is possible, but I'm not sure how. I'd love to be able to understand how to do this, and solve my current problem.
To do the same thing without writing a file to disk, you might look into the MemoryStream class. As you'd guess, it streams data from memory like the FileStream does from a file. The two main steps would be:
Take your object in memory and instead of writing it to a file, you'd serialize it into a MemoryStream using a BinaryFormatter or other method (see that topic on another StackOverflow Q here: How to convert an object to a byte array in C#).
Pass the MemoryStream to the StreamContent method, exactly the same way you're passing the FileStream now.
I am making a Windows Phone app and I am trying to get JSON data from a URL. The user needs to be logged into the website (which hosts the JSON data) in order to get JSON data and I cannot use the Web Browser control to display the data and then extract the string since the browser doesn't recognize it (for some weird reason) and asks to search for an app on Store which can handle that JSON file type. (If I open the URL in desktop browser on my Windows PC, I can see the raw JSON data). I can't use normal HTTPWebRequest or WebClient as to get JSON data the login cookies needs to be set (the JSON data is user-specific) and I can't extract the cookies from Web browser control and use it with WebClient or HTTPWebRequest. So the best thing I can do is use a special internal instance of IWebRequestCreate that is used internally by the WebBrowser. By opening background HTTP requests with that class, the cookies get automatically set as if they were created/sent by the WebBrowser control. But my code is not returning the JSON data, I get blank response, as in the string resp is empty.
Below is the code:
Dim browser = New WebBrowser()
Dim brwhttp = GetType(WebRequestCreator).GetProperty("BrowserHttp")
Dim requestFactory = TryCast(brwhttp.GetValue(Browser, Nothing), IWebRequestCreate)
Dim uri = New Uri("http://api.quora.com/api/logged_in_user?fields=inbox,notifs,following,followers")
Dim req = requestFactory.Create(uri)
req.Method = "GET"
req.BeginGetResponse(New AsyncCallback(AddressOf request_Callback), req)
Private Sub request_Callback(asyncResult As IAsyncResult)
Dim webRequest As HttpWebRequest = DirectCast(asyncResult.AsyncState, HttpWebRequest)
Dim webResponse As HttpWebResponse = DirectCast(webRequest.EndGetResponse(asyncResult), HttpWebResponse)
Dim tempStream As New MemoryStream()
webResponse.GetResponseStream().CopyTo(tempStream)
Dim sr As New StreamReader(tempStream)
Dim resp As String = sr.ReadToEnd
End Sub
What's wrong?
I found that CopyTo can leave the Stream's pointer at the end of the buffer, you probably need to reset tempStream's pointer to the beginning before attempting to read it with the StreamReader, here's the code...
webResponse.GetResponseStream().CopyTo(tempStream);
tempStream.Seek(0, SeekOrigin.Begin);
Dim sr As New StreamReader(tempStream);
i want to get the html Source code of website,
it something like:
wb.Document...
1:
webbrowser1.document.body.innerhtml
2:
Dim webClient As New System.Net.WebClient
Dim result As String = webClient.DownloadString("http://www.google.co.il")
;)
Below is the example code I'm using to get this to work and it does work if I try to read yahoo.com.
Here is the problem. The address I need to read is a java servlet that processes parameters passed in, generates a text document on the server, and then redirects to another URL and returns the address of the text file on the server. I then need to download that text file and process it. I'm having problems connecting to the first URL with the parameters and I think it has to do with the redirect.
I'm using the WebRequest object and I've tried using the HttpWebRequest object. Are there any other objects that support redirects?
TIA
Dim reader As StreamReader
Dim request As WebRequest
Dim response As WebResponse
Dim data As String = ""
Try
request = WebRequest.Create("URL Here")
request.Timeout = 30000
response = request.GetResponse()
reader = New StreamReader(response.GetResponseStream())
data = reader.ReadToEnd()
Catch ex As Exception
MsgBox(ex.Message)
End Try
Return data
Edit
I just tested out HttpWebRequest.Create() and that does handle the 301 and 302 fine with out extra code.
Can you post the error you are seeing
You could cast the WebResponse to a HttpWebResponse:
I need to convert this to VB... but it might help you start:
var response = request.GetResponse() as HttpWebResponse;
if (response.StatusCode == HttpStatusCode.Moved || response.StatusCode == HttpStatusCode.Redirect)
{
// Follow Redirect, new request based off Redirect
}
// Read Data
I believe you just have to set the AutoRedirect property.
request.AutoRedirect = true;
webRequest = webRequest.Create(URL)
webresponse = webRequest.GetResponse()
inStream = New StreamReader(webresponse.GetResponseStream())
Read URL full source code
winston
I think I found something that will work.
I used a WebBrowser control instead.
Have a button that runs this code...
WebBrowser1.Navigate("URL Here")
And this function to process once the request returns.
Private Sub WebBrowser1_Navigated(ByVal sender As System.Object, ByVal e As System.Windows.Forms.WebBrowserNavigatedEventArgs) Handles WebBrowser1.Navigated
MsgBox(WebBrowser1.DocumentText)
End Sub