vb.net htmlagilitypack loop of selectnode
Question
i made an array of links
Dim horof As String = "A B C D"
Dim alphabarray As String() = horof.Split(New Char() {" "c})
Dim urls() As String = alphabarray.Select(Function(o) "http://somelink/list-" & o).ToArray()
the output is like this
http://somelink/list-A
http://somelink/list-B
http://somelink/list-C
http://somelink/list-D
thin i made webrequest for each link like this :
For i As Int32 = 0 To urls.Length - 1
Dim wRequest As WebRequest
Dim WResponse As WebResponse
wRequest = FtpWebRequest.Create(urls(i))
WResponse = wRequest.GetResponse
Dim SR As StreamReader
SR = New StreamReader(WResponse.GetResponseStream)
urls(i) = SR.ReadToEnd
Next
now i have html source of all the links in array of string that is urls and i want to use htmlagilitypack to selectnodes from each html source in the array
Dim htmlDoc As New HtmlDocument()
htmlDoc.LoadHtml(urls)
Dim wantednode = htmlDoc.DocumentNode.SelectNodes("Xpath")
but it didnt work
i try to pu it in the same loop
Dim htmlDoc As New HtmlDocument()
Dim wantednode As HtmlNodeCollection
For i As Int32 = 0 To urls.Length - 1
Dim wRequest As WebRequest
Dim WResponse As WebResponse
wRequest = FtpWebRequest.Create(urls(i))
WResponse = wRequest.GetResponse
Dim SR As StreamReader
SR = New StreamReader(WResponse.GetResponseStream)
urls(i) = SR.ReadToEnd
htmlDoc.Load(urls(i))
wantednode = htmlDoc.DocumentNode.SelectNodes("Xpath")
next
this didnt work too how to make loop of wantednode = htmlDoc.DocumentNode.SelectNodes("Xpath") for each htmlcode in the urls array
each html code in urls array are like this that came from
<body>
<div class="list_body">
<ul class="listing">
<li>
<a href="http://wanted1.com" title="">title1 </a>
</li>
<li>
<a href="http://wanted2.com" title="">title2 </a>
</li>
<li>
<a href="http://wanted3.com" title="">title3 </a>
</li>
<li>
<a href="http://wanted4.com" title="">title4 </a>
</li>
<li>
<a href="http://wanted5.com" title="">title5 </a>
</li>
<li>
<a href="http://wanted6.com" title="">title6 </a>
</li>
</ul>
</div>
</body>
i want http://wanted2.com link in every string in urls
2 answers
solution1
1 2016-03-11 18:10:40
Here is some library code I use:
Public Function Web_Request_Response(URL As String) As String
Try
Dim myRequest As HttpWebRequest
Dim myResponse As HttpWebResponse
Dim sr As StreamReader
Dim sResponse As String = ""
myRequest = CType(WebRequest.Create(URL), HttpWebRequest)
myResponse = CType(myRequest.GetResponse(), HttpWebResponse)
sr = New StreamReader(myResponse.GetResponseStream())
sResponse = sr.ReadToEnd.ToString
Return sResponse
Catch ex As Exception
LogMsgBox(ex, ex.Message, , "WebRequest_Responce Error")
Return ""
End Try
End Function
It differs slightly from your calls. Perhaps something to do with the type casting? FTP vs HTTP?
Nice use of Linq.
You can save some typing:
Dim alphabarray As String() = horof.Split(New Char() {" "c})
--- same as ---
Dim alphabarray As String() = horof.Split({" "c})
or
Dim alphabarray As String() = horof.Split(" ")
solution2
1 ACCPTED 2016-03-12 03:35:11
You're supposed to use HtmlDocument.LoadHtml() instead of HtmlDocument.Load() , since you want to populate the HtmlDocument from an HTML string :
'urls(i) value has been replaced with HTML string by the following line..
urls(i) = SR.ReadToEnd
'..so next, you need to use `LoadHtml()`
htmlDoc.LoadHtml(urls(i))
wantednode = htmlDoc.DocumentNode.SelectNodes("Xpath")
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