Cefsharp: Get hyperlinks from document - vb.net

I am used to getting hyperlinks in a document like this:
Dim html As String =
"var linksArray = new Array(); " &
"for (var i = 0; i < document.links.length; i++) {" &
"linksArray[i] = [String(document.links[i].innerHTML), String(document.links[i].innerText), String(document.links[i].href)];" &
"} " &
"return linksArray;"
Try
Dim linksArray As JSArray = _Browser.WebView.EvalScript(String.Format("(function(){{ {0} }})()", html))
For Each obj As Object In linksArray
Dim sInnerHTML As String = obj(0).ToString().Trim()
Dim sInnerText As String = obj(1).ToString().Trim()
Dim sHRef As String = obj(2).ToString().Trim()
Dim nItem As New clsURL
nItem.HRef = sHRef
nItem.InnerHTML = sInnerHTML
nItem.InnerText = sInnerText
nList.Add(nItem)
Next
However, CefSharp does not have JSArray.
Can anybody tell me what would be the way to do that with CefSharp?
Thank you!

Have a read over the FAQ, particularly https://github.com/cefsharp/CefSharp/wiki/Frequently-asked-questions#2-how-do-you-call-a-javascript-method-that-return-a-result
EvaluateScriptAsync will return a List<object> (in yours case each entry will likely be another List<object as you've got nested arrays)
I've created a Gist as an example, it's in C#, you should be able to port it to VB.Net (I cannot help you there)
https://gist.github.com/amaitland/9d354376960b0cd9305a
(I plan to add a slightly more detailed example to the FAQ, so yours case seems like a reasonable candidate).
As a side note, when executing blocks of code using EvaluateScriptAsync I recommend using an anonymous closure.

Related

VB.Net Cant create "new line" "string"

I am in need of assistance... i am trying to create a textfile with links in it. the code i have..
dim domain as string = "http://www.mywebsite/"
dim name as string = "username"
Dim link As String = New String("domain" & "name")
TextBox1.AppendText(link & Environment.NewLine)
Msgbox(textBox1.lines(0))
The problem is that MsgBox only shows up as "http://www.mywebsite/". the textbox does show "http://www.mywebsite/username" but when copied to text document it is:
Line0: http://www.mywebsite/
Line1:username
any ideas... tried using
Dim link As String = String.Join(domain & name) but that doesnt work nor does
Dim link As String = new String.Join(domain & name)
i need
Msgbox(textBox1.lines(0)) to display "http://www.mywebsite/username" not one or the other.
That was quick got a message saying to use. Dim link As String = String.Concat(domain & name)
i think you should move to StringBuilder first import Imports System.Text
'create a string with multiple lines
Dim a As New StringBuilder
a.AppendLine("hi")
a.AppendLine("there")
a.AppendLine("this")
a.AppendLine("is")
a.AppendLine("a")
a.AppendLine("test")
'read will makes read line by line
Dim read As String() = a.ToString.Split(vbNewLine)
'count has number of lines
Dim count As Integer = a.ToString().Split(vbNewLine).Length - 1
'lines will be added to combobox one by one
For i As Integer = 0 To count - 1
ComboBox1.Items.Add(read(i))
Next
you just should edit it to suits your needs i didnt understand what you needed exactly

Adding multiple strings to a listbox from text

I have a text file I need to get multiple strings from, I can sort of do it but it only shows the first string in the listbox
When we tried with XML reader it was collecting everything in the XML that was tagged Object Identifier along with the cameras
I need to look for lines similar to the following, there could be any amount
Object Identifier="./Cameras/MyCamera" Label="Standard Camera" Name="MyCamera" Type="Camera"
key identifiers:
./Cameras/
Label="Standard Camera"
Type="Camera"
I could use "MyCamera" after ./Cameras/ or Name="MyCamera" both of these are common in each occurrence of the lines
in my example below it has the file I wish to read it should list 3 cameras
https://www.dropbox.com/s/dy7r2auf9vv0m7g/testvb.zip
The XML is generated by Thea render, its the scene file with the model, lights etc taken out so it just leaves cameras and some core settings
Thanks to varocarbas, this is the code that solves my problem:
Dim path As String = "C:\Users\jen\Desktop\test\temp.xml"
Dim settings As System.Xml.XmlReaderSettings = New System.Xml.XmlReaderSettings()
settings.ConformanceLevel = System.Xml.ConformanceLevel.Fragment
Using reader As System.Xml.XmlReader = System.Xml.XmlReader.Create(path)
While (reader.Read())
If (reader.NodeType = System.Xml.XmlNodeType.Element) Then
If (reader.Name = "Object") Then
'Object Identifier="./Cameras/MyCamera" Label="Standard Camera" Name="MyCamera" Type="Camera"
Dim Identifier As String = reader.GetAttribute("Identifier") '"./Cameras/MyCamera"
Dim Label As String = reader.GetAttribute("Label") '"Standard Camera"
Dim Name As String = reader.GetAttribute("Name") '"MyCamera"
Dim Type As String = reader.GetAttribute("Type") '"Camera"
Dim wholeString As String = Name 'WHOLE STRING TO BE ADDED TO THE LISTBOX
'Adding the string to ListBox1
If (wholeString.Trim.Length > 0) And Type = "Camera" Then
ListBox1.Items.Add(wholeString)
End If
End If
End If
End While
End Using
You can use the XMLReader I proposed in another answer and do the following modifications on it:
Dim path As String = "temp.txt"
Dim settings As System.Xml.XmlReaderSettings = New System.Xml.XmlReaderSettings()
settings.ConformanceLevel = System.Xml.ConformanceLevel.Fragment
Using reader As System.Xml.XmlReader = System.Xml.XmlReader.Create(path)
While (reader.Read())
If (reader.NodeType = System.Xml.XmlNodeType.Element) Then
If (reader.Name = "Object") Then
'Object Identifier="./Cameras/MyCamera" Label="Standard Camera" Name="MyCamera" Type="Camera"
Dim Identifier As String = reader.GetAttribute("Identifier") '"./Cameras/MyCamera"
Dim Label As String = reader.GetAttribute("Label") '"Standard Camera"
Dim Name As String = reader.GetAttribute("Name") '"MyCamera"
Dim Type As String = reader.GetAttribute("Type") '"Camera"
Dim wholeString As String = Identifier & " - " & Label & " - " & Name & " - " & Type 'WHOLE STRING TO BE ADDED TO THE LISTBOX
'Adding the string to ListBox1
If (wholeString.Trim.Length > 0) Then
ListBox1.Items.Add(wholeString)
End If
End If
End If
End While
End Using
This code retrieves all the information you want and stores it in LisBox1 by putting " - " to separate each element. This is information more than enough and you should be the one performing any further change, for example: converting "./Cameras/MyCamera" into "./Cameras/" (there is an indication of how to do that in my previous code); or change the way the different items are displayed in the listBox (or perhaps you want to include one listBox per element: one for identifiers, another for labels, etc.).

Loading Picture Stored in Access Database into Program VB.NET

I have an Access Database linked with a VB project through a data source. In the database on one of the tables, I have an OLE Object field. I have saved pictures in .BMP format and .JPG format in this field. The problem I am encountering is loading this image into my application. This is what I would like to be able to do:
ButtonMeal1.BackgroundImage = IPOSDBDataSet.Meals.Rows(0).Item(5)
Where Item(5) is the column of the row where the image is stored.
Is there another way of doing this. Do I have to load the picture into the program by storing it as a variable, and then using that to change the background image of the button. There are no clear answers on the internet regarding my issue. Please help!
EDIT 1:
After doing some more research, I found some code and adjusted it to try fix my problem.
Dim ImageByteArray As Byte() = CType(IPOSDBDataSet.Meals.Rows(0).Item(5), Byte())
Dim ImageMemoryStream As MemoryStream = New IO.MemoryStream(ImageByteArray)
Dim MyImage As Image = Drawing.Image.FromStream(ImageMemoryStream)
PictureBox1.Image = MyImage
However, I receive the error "Parameter is Not Valid" with the 3rd line of the code. Would anyone be able to tell me how I could adjust my code to fix this issue, or tell me if I am doing something completely wrong?
EDIT 2:
I keep on changing the code around, but the error is always "Parameter is not valid.". What parameter is not valid?
EDIT 3:
No matter what I change it to, the error still persists. What is this parameter that is causing all my issues?
Dim ImageByteArray As Byte() = CType(IPOSDBDataSet.Meals.Rows(0).Item(5), Byte())
Dim ImageMemoryStream As MemoryStream = New IO.MemoryStream(ImageByteArray)
Dim ImageStream As Stream = ImageMemoryStream
Dim MyImage As Image = Drawing.Image.FromStream(ImageStream)
PictureBox1.Image = MyImage
EDIT 4:
Can anyone please help? I really need to be able to implement this into my program. Is there any other possible way of storing images in an access database, and importing them into my vb.net program?
Credit goes to TnTinMan from CodeProject for the answer. Hopefully this helps someone else:
Dim ImageByteArray As Byte() = CType(DataSet.Table.Rows(RowNo).Item(ItemNo), Byte())
Dim ImageMemoryStream As MemoryStream = New IO.MemoryStream(GetImageBytesFromOLEField(ImageByteArray))
Dim MyImage As Image = Drawing.Image.FromStream(ImageMemoryStream)
Friend Shared Function GetImageBytesFromOLEField(ByVal oleFieldBytes() As Byte) As Byte()
Dim BITMAP_ID_BLOCK As String = "BM"
Dim JPG_ID_BLOCK As String = ChrW(&HFF).ToString() & ChrW(&HD8).ToString() & ChrW(&HFF).ToString()
Dim PNG_ID_BLOCK As String = ChrW(&H89).ToString() & "PNG" & vbCrLf & ChrW(&H1A).ToString() & vbLf
Dim GIF_ID_BLOCK As String = "GIF8"
Dim TIFF_ID_BLOCK As String = "II*" & ChrW(&H0).ToString()
Dim imageBytes() As Byte
' Get a UTF7 Encoded string version
Dim u7 As System.Text.Encoding = System.Text.Encoding.UTF7
Dim strTemp As String = u7.GetString(oleFieldBytes)
Dim st2 As String = System.Text.Encoding.UTF8.GetString(oleFieldBytes)
' Get the first 300 characters from the string
Dim strVTemp As String = strTemp.Substring(0, 300)
' Search for the block
Dim iPos As Integer = -1
If strVTemp.IndexOf(BITMAP_ID_BLOCK) <> -1 Then
iPos = strVTemp.IndexOf(BITMAP_ID_BLOCK)
ElseIf strVTemp.IndexOf(JPG_ID_BLOCK) <> -1 Then
iPos = strVTemp.IndexOf(JPG_ID_BLOCK)
ElseIf strVTemp.IndexOf(PNG_ID_BLOCK) <> -1 Then
iPos = strVTemp.IndexOf(PNG_ID_BLOCK)
ElseIf strVTemp.IndexOf(GIF_ID_BLOCK) <> -1 Then
iPos = strVTemp.IndexOf(GIF_ID_BLOCK)
ElseIf strVTemp.IndexOf(TIFF_ID_BLOCK) <> -1 Then
iPos = strVTemp.IndexOf(TIFF_ID_BLOCK)
Else
Throw New Exception("Unable to determine header size for the OLE Object")
End If
' From the position above get the new image
If iPos = -1 Then
Throw New Exception("Unable to determine header size for the OLE Object")
End If
imageBytes = New Byte(CInt(oleFieldBytes.LongLength - iPos - 1)) {}
Array.ConstrainedCopy(oleFieldBytes, iPos, imageBytes, 0, oleFieldBytes.Length - iPos)
Return imageBytes
End Function
There isn't really such a thing as an 'image' stored in an Access table, only a binary stream. Therefore, the left hand side of your expression doesn't know that the right hand side is providing an image. You would have to stream the binary stream into a stream in VB.NET, then use System.Graphics methods to make it into a BMP or PNG or whatever. You could assign that object to the button.
still show error: index and length must refer to a location within the string.Parameter name: len

VB - Issue using XPath reading an XML

I am currently trying to read in an XML node from a filepath which I pass to my method.
Public Function ReadXMLForIsite(xmlFileName As String)
Dim IsitePath As String
Dim doc As New XPathDocument(xmlFileName)
Dim nav As XPathNavigator
Dim iter As XPathNodeIterator
nav = doc.CreateNavigator
iter = nav.Select("GovTalkMessage/Header") 'Node name
'Loop through the records in that node
While iter.MoveNext
Dim lstNav As XPathNavigator
'Get the data we need from the node
Dim iterNews As XPathNodeIterator
lstNav = iter.Current
iterNews = lstNav.SelectDescendants(XPathNodeType.Element, False)
'Loop through the child nodes
While iterNews.MoveNext
Debug.WriteLine(iterNews.Current.Name & ": " & iterNews.Current.Value)
End While
End While
Return IsitePath
End Function
Every time i run this method (even with different node names) the variable 'iter' states that 'debugger display proxy is a type and cannot be used as an expression'. This occurs just before the while statement, therefore does not go in. Any help would be much appreciated. Thanks!
Try to load your Xml into an XDocument.
Dim xdoc As XDocument = XDocument.Load("X:\Jacob.Freeman\RTI\TestXML\0001R.xml")
Dim headerNode = xdoc.Descendants.First(Function(x) x.Name.LocalName = "Header")
For Each desc In headerNode.Descendants()
Console.WriteLine(desc.Name.LocalName + ":" + desc.Value)
Next
Console.ReadLine()

Dynamic variable in VB.NET

I need to pass a variable by name like this
Dim html_news = "...the news ..."
Dim var = "news"
Dim a = "html_" & var
' content of that variable
How can I do that in VB.NET ?
vb.net doesn't really lend itself to what you need to do - you could have done that sort of thing in scripting languages like classic asp and JavaScript. Although it might not have been the 'right' way to do it - the use of the 'eval' function is frowned on in Javscript as it's a security risk. I think the code below will do what you need in a way that's more in keeping with the way that vb.net works -
Dim d As New Dictionary(Of String, String)()
Dim html_news = "...the news ..."
d.Add("html_news","...the news ...")
Dim var = "news"
Dim a = d("html_" & var)