Code:
Public Function ScreenScrapeHtml(ByVal url As String) As String
Dim objRequest As WebRequest = System.Net.HttpWebRequest.Create(url)
[code]...
If it cant reach a URL it will give me this error:
Code:
Webexception was unhandeled:
Dim sr As New StreamReader(objRequest.GetResponse().GetResponseStream())
How I can add some error-handling to this code? Like if it cant reach a URL.
i want to make a website builder which has the html code already written so all you have to do is check which boxes you want and click next or back to go through the process of making a website with specific code implemented in it.
P.s. im using VB 2008 express edition?
I have tried a few things like converting HTML to XML and then using an XML navigator to get input elements but I get lost whenever I start this process.What I am trying to do is to navigate to a website which will be loaded using textbox1.text.Then download the html and parse out the input elements like . username, password, etc and place the element by type (id or name) into the richtextbox with the attribute beside the name.[code]Any clues or how to properly execute an HTML to XML conveter, reader, parser?
View 2 RepliesI have a routine that is called when an unhandled exception occures.It is called by the MyApplication_UnhandledException method in applicationEvents (which handles Me.UnhandledException)
I am looking for some code that manages disects the data provided to generate information that is of benefit to the debugging team.
When two computers are connected through TCP, and one of them closes and breaks the connection, it throws error 10054 "Remote host forcibly closed the connection".I want to handle this error because I know it will happen more often than not with the application I'm building. In System.Net.Sockets.SocketException, there is an on the error code. But when I run the program, the exception that is being thrown is System.IO.IOException, and the GetType for IOException is the socket exception. I don't know how to handle the socket exception if it's not the root cause of the exception.
Here is the code for my Try Catch block:
For infiniteCounter = 1 To 2
infiniteCounter = 1
[code].....
I have a delete button in a datagridview. The button works fine however when there is nothing to delete it throws an index out of range exception. Now I know for a fact people are going to click that button even though there is nothing the I am presuming the best course of action is going to be a try/catch but I am not sure how to do it. My code is as follows,
Private Sub DataGridView1_CellContentClick(ByVal sender As System.Object, ByVal e As System.Windows.Forms.DataGridViewCellEventArgs) Handles DataGridView1.CellContentClick
If e.ColumnIndex <> 7 Then
[code].....
This may sound really stupid but I have to ask cause I'm not finding this answer anywhere.I have an application where the user will need to sign up for a new user account on the website [URL]..However when I am using Firefox's plug-in Firebug to view html I am getting something totally different than when I just right click on the site and view the page source.
What I am trying to do is to get the captcha from the website and display it in a picturebox on the application so the user can view the captcha, solve the captcha and then the app post is back to the service for a response.
Here is the source that I am getting using Firefox's Firebug to inspect the element:
<td>
<input type="hidden" value="Oo3Jo1I8bgzK68agMqo3s79ZZib2OkbK" name="iden">
<img class="capimage" src="/captcha/Oo3Jo1I8bgzK68agMqo3s79ZZib2OkbK.png" alt="i wonder if these things even work">
</td>
[Code]...
Why would the two be showing me two different versions of the HTML?
And how would you be able to grab that source to view in a picturebox using webclient?
I have a TextBox and I want to allow VB syntax, but when I run the site and try to save the VB code to the database, I am getting an error. I believe the error has something to do with the VB code.I have put the httpRuntime requestValidationMode="2.0" setting in my web.config, and I've added validateRequest="false" in the directive at the top of the page, but it didn't resolve the issue.
View 1 RepliesI am trying save a value from an input tag in some HTML source code. The tag looks like so:
<input name="user_status" value="3" />
I have the page source in a variable (pageSourceCode), and need to work out some regex to get the value (3 in this example). I have this so far: [Code] Which works fine most of the time, however this code is used to process source code from multiple sites (that use the same platform), and sometimes there are other attributes included in the input tag, or they are in a different order, eg:
<input class="someclass" type="hidden" value="3" name="user_status" />
I just dont understand regex enough to cope with these situations.
How can you programmatically get a websites inner html? I found a way of getting the html of a site, but dont know how to get the inner html.
View 11 RepliesI have an object, say Order where if an error occurs, it raises the ErrorOccurred event. If I'm running some code in say, the codebehind for a .aspx page with an public Order registered as WithEvents and I want to check to see if an error has occurred before I run more code, how do I do this? I can't simply check theOrder.ErrorOccurred. Do I have to create a local boolean flag that switches over in the event handler (OnErrorOccurred)?
Example:
Public WithEvents theOrder As New Order
Public Sub DoStuff()
theOrder.DoSomething()
If theOrder.ErrorOccurred Then
[code]....
I need to create a VB.net app that automatically reads a html table. It should connect to a web address (eg "[URL]") and read it. I'll be happy if I could just get the full HTML. I was able to use this code to get the HTML of a regular website:
Dim strReply As String = "NULL"
Dim objHttpRequest As HttpWebRequest
Dim objHttpResponse As HttpWebResponse
objHttpRequest = HttpWebRequest.Create("[URL]")
objHttpResponse = objHttpRequest.GetResponse
Dim objStrmReader As New StreamReader(objHttpResponse.GetResponseStream)
strReply = objStrmReader.ReadToEnd()
This code sample will give me the HTML for the website [URL]. However it will not work with the website I want (eg "[URL]"), because when you access it via regular browser it will popup a browser dialog asking for credentials (user / pass). So when I run the code above for it, I'll get the exception:
The remote server returned an error: (407) Proxy Authentication Required.
How do I set this up to use the credentials, before retrieving the HTML? This is actually my first web-related app.
Eventually, I'm going to want/need the program I am creating to either:
A. Access the MySQL database from my website.
Or.
B. 'Load' a PHP page, and grab the contents off of it. [URL]Are these options avaiable in VB.NET ?
I have a website that divided into 4 frames. I'm trying to create an application that will constantly run on my PC as a task looking for certain text in the HTML in a frame.When it finds the text it would alert the user by presenting a pop-up message. This is basically a monitoring website that checking network nodes. Instead of staring at the screen looking for critical messages I would like to be notified when there is an alert.
View 1 Replieshow i can read text or HTML from a website opened in IE?
This is the code i'm trying to use:
For Each ie As InternetExplorer In New ShellWindowsClass()
HTML = ie. ???
Next
I want to read the HTML code of the page into a string.
Like in firefox or Internet Explorer where you can right click and view the html page source how can you do this in an app?I have a web browser in the form and I'm trying to view the web page in the web browser and then view the source code of that page in a box below it.
View 8 RepliesI am trying to extract everything between the body part as I am building a forum crawler
and since all the user posts are between the <body></body> I have chosen to experiment
with Regex. So far I have coded the following but sort of stuck on how to output the result say in a textbox? Also I am not sure if the body part of the regex is correct.
Dim URL As String = Textbox1.Text
Dim request As System.Net.HttpWebRequest = System.Net.HttpWebRequest.Create("URL")
Dim response As System.Net.HttpWebResponse = request.GetResponse
Dim streamReader As System.IO.StreamReader = New System.IO.StreamReader(response.GetResponseStream())
[Code] .....
So, in this program I added 2 necessary login codes let's say, first a code that I will provide and then the username and password from my website. I implemented both ways, the first one worked perfectly, however, the second one is giving me some problems, my idea for that control was not using a database of users, that was going to be too complicated for a 14 year old guy, so I decided to take the source code for my website and I took a fragment, the boxes for the login, username, password, forgot your password, remember me and some other boxes, great, that worked perfectly, I uploaded the HTML modified document to my website's files and linked it to the URL of the webbrowser control in one new form, good, it's working, but I wanted a simple condition that works for this function "When the webbrowser loads the success website, hide me and show the past login form, when this one shows the failed login, popup a messagebox that says the error.". I have been looking for that simple condition for a long time. I am using Visual Basic 2010 Express Edition.
View 4 RepliesI was trying to use HtmlDocument and a given url to pull in the html contents of a website to use. However there is no constructor for HtmlDocument and it's Url property is readonly. Is there any way to create an object that contains the entire DOM for a given url?
View 2 RepliesI wondered if someone could help me with my code. I am changing some pages of a website from Excel documents to HTML form.I have most of the code sorted but I also need to save a few documents to Word. I keep getting a few errors and cannot seem to solve them.
I have included my code and highlighted the errors by underlining them. Maybe someone can help??
Imports Microsoft.Office.Interop
Imports Microsoft.Office.Interop.Excel
Public
Class Form1
Dim path
[Code]...
I have a multilingual company website (Visual Studio / VB / ASP.NET 4.0), and when, on the homepage, you click a flag, the text changes to that language and stays with you the entire session, after I made a class, BasePage.vb. Everything works great, but the URL never changes .... clients.aspx remains clients.aspx although the text DOES switch to Dutch.
It's been recommended by @Aritstos to make it so it looks like clients.aspx?lang=nl as opposed to just clients.aspx in another language.
Currently, my asp homepage hyperlinks that work look like this:
<asp:LinkButton ID="LinkButton7" runat="server"
CommandArgument="nl" OnClick="RequestLanguageChange_Click"
class="flagbutton">
[Code]....
what i am trying to do is extract information beween two tags in some html from the source of a website. The contents of the text between the two tags will always be different. the code i currently have is;
[Code]...
I have some VB6 code that instantiates a class which handles events that are being raised from a VB.NET component. The VB6 is pretty straightforward:private m_eventHandler as new Collection
public sub InitSomething()
dim handler as EventHandler
set handler = new EventHandler
m_eventHandler.Add handler
m_engine.Start
[Code]...
My problem is that when I debug the VB6 program, the first time InitSomething gets called, the event will not be handled (the VB6 event handler is never entered). Subsequent calls to InitSomething does work.
Everything works as I would have expected when I run the program outside the debugger. At this point, I'm not even sure if this is something I should be worried about.It may or may not be relevant but the VB.NET was converted from a VB6 using the Visual Studio code conversion tool (and subsequently manually cleaned up).
What error handling should be used in VB.NET? Should one use the "On Error Goto ErrorHandler Exit Sub ErrHandler ... End Sub" pattern or should you use the "try {... } catch {...} finally {... }" pattern?
View 4 RepliesIn my vb.net application if I have a known set of Error Strings i.e.
Failed because I don't know about it
Failed because I know about it but I can't find it
Failed for another reason
[code].....
I am just doing a bit of error handling. I am just check to make sure that a user has selected an option within a combo box (named cbtitle1) and if option has not been selected throw an error message to tell the user.this if statement is within a save button which once a user click save this error checking runs first then if combo box has an option selected the save goes ahead else it throws an error.I can stop the save function OK but I wanted to put a error icon in with the message box but I get an error when I add it.[code]
View 3 RepliesObviously error handling is a major factor in making a good application. If a error happens letting a user know what has gone wrong.But some times error handling may(i think) not be needed. Example.
Private Sub RemoveCheckedl()
Try
For Each Item As ListViewItem In lst.CheckedItems[code]....
also when error handling it's could to think about what type of errors could be made.
Catch ex As Exception
MessageBox.Show(ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error)
even though this catches the error and displays a msg, it may not be a great message for the user so he/she can understand.
I am working on an executable to load set of data into databases.I will be running it as a windows service. I will be doing several different checks to see if the fields exists in the incoming files. When i do the checks using if statements.I would like to stop processing when a major error occurs or when any thing is interrupted Like say windows crashed. I would like to create an error file with the error message in it for that particular file. I would be monitoring error folder everyday to check if there are any errors.
View 1 RepliesWhen debugging a program, instead of doing this on EVERY piece of code:
Try
MyFunction()
Catch ex as Exception
MsgBox(ex.Message)
End Try
Is there a way to apply that to everything error I encounter without writing it on every function/sub/etc?
The info i need extracted is formatted:
<TD><A HREF="http://xxxxx.com/xxxxxx/index.html"><IMG SRC="../xxxxx/thumbnails/xxxxx.jpg"> </A></TD>
<TD>=== <B><A HREF="http://xxxxxxxxx.com/xxxxxxxx/index.html">LINE 0</A></B> ===<BR>
<FONT SIZE="2" COLOR="#400080">
[code]....
how do i extract the info between TD=== and /a and Line 1,2, and 3 and store it into a database from a live website?
