Conversion vb6 source to visual basic.net 2010

Dim FName As String   ' FileName of the html file
Dim LeftX As Integer   ' Global x coordinate for the nodes in html
Dim TopY As Integer    ' Global Y coordinate for nodes in html
Dim totalHTML As String ' this variable holds the HTML code generated throughout the program
Const TopIncrement = 20   ' the number of pixels of difference between nodes
Const LeftIncrement = 30


Public Function WriteTextFileContents(TeXt As String, FileName As String)
' Simple Function writes text to a file
' Used for outputing to html format
    Dim fNum As Integer, isOpen As Boolean
    On Error GoTo ErrHandle
    fNum = FreeFile()
        Open FileName For Output As #fNum
        isOpen = True
        Print #fNum, TeXt
ErrHandle:
        If isOpen Then Close #fNum
End Function

Public Function ReadTextFileContents(FileName As String) As String
    ' Simply Reads a text file
    Dim fNum As Integer, isOpen As Boolean
    On Error GoTo ErrHandle
    fNum = FreeFile()
    Open FileName For Input As #fNum
    isOpen = True
    ReadTextFileContents = Input(LOF(fNum), fNum)
ErrHandle:
    If isOpen Then Close #fNum
End Function

Private Function horizontalline(top, x1, x2)
    ' Returns VML (Vector Markup language) equivalent
    ' Of a horizontal line
    Dim width
    If x1 > x2 Then width = x1 - x2 Else width = x2 - x1
    horizontalline = "<v:rect style='removed:absolute;removed" & x1 & ";removed" & top & ";width:" & width & "px;height:1px;Z-INDEX: 0;'></v:rect>"
End Function

Private Function verticalline(left, y1, y2)
    ' Returns VML (Vector Markup language) equivalent
    ' Of a vertical line
    Dim height
    If y1 > y2 Then height = y1 - y2 Else height = y2 - y1
    verticalline = "<v:rect style='removed:absolute;removed" & left & ";removed" & y1 & ";width:1px;height:" & height & "px;Z-INDEX: 0;'></v:rect>"
End Function

Public Function SaveAllChildrenOf(indexOfNodeToBePrinted As Integer, htmlFileName As String)
    ' The main public function . Does three things
    ' Firstly, Initializes the program and the html file
    Initialise htmlFileName
    ' Secondly calls the recursive function to convert the nodes to html
    PrintNode indexOfNodeToBePrinted
    ' This statement to write the html to a file
    WriteTextFileContents totalHTML, htmlFileName
End Function

Private Function PrintNode(NodeIndex As Integer)
    ' First one of the two recursive functions that go through the tree
    
    TopY = TopY + TopIncrement ' this topY variable maintains the Y coordinates of the nodes in html
    Form1.Tree.Nodes(NodeIndex).Tag = TopY 'Storing the Y coordinates in the Tag part of the treeview control so that they can be refrenced later by their last children
    WriteHTML Form1.Tree.Nodes(NodeIndex).TeXt ' This functions just produces html at the current x and y coordinates and increments the y coordinate
    
    If NodeIndex <> 1 Then  ' SInce the first node would not have parent
        If Form1.Tree.Nodes(NodeIndex).index = Form1.Tree.Nodes(NodeIndex).Parent.Child.LastSibling.index Then  ' This means if this is the last child of its parent then
             totalHTML = totalHTML & verticalline(LeftX - LeftIncrement + 3, Int(Form1.Tree.Nodes(NodeIndex).Parent.Tag) + 7, TopY + 7)  ' then draw a vertical line from parents y (as stored in tag property(see Above)) coordinate to its Y coordinate (A shift of 7 pixels is given to improve looks)
        End If
    End If

    
    PrintAllChildren (NodeIndex) ' this function goes through all the children of this node and calls the current method for each children.
End Function

Private Function PrintAllChildren(index As Integer)
    ' What this function does is that it calls the above function for all the children of the node specified
    ' So these two functions basically call each other to go through the whole tree
    If Form1.Tree.Nodes(index).Children = 0 Then Exit Function ' No use of the function if it doesnt even have children
    
    LeftX = LeftX + LeftIncrement ' The children should be a little to the left of the parent. Dont you think?
    Dim curIndex As Integer 'This would be the Index of the current child
    curIndex = Form1.Tree.Nodes(index).Child.index 'getting its childs index
    For f = 1 To Form1.Tree.Nodes(index).Children ' for all children
        PrintNode (curIndex) 'call the above function
        If f <> Form1.Tree.Nodes(index).Children Then curIndex = Form1.Tree.Nodes(curIndex).Next.index ' if we are not at the last child then goto next child
    Next
    LeftX = LeftX - LeftIncrement ' after all the children have been displayed (And their children have been displayed), back to the old X coordinate
End Function

Private Function WriteHTML(TeXt As String)
    ' Simple function to use <div> tags and style sheets to put the node at a specific x and y coordinate in the web page
    totalHTML = totalHTML & "<div style='{BACKGROUND-COLOR: white;color:black;Z-INDEX: 1;removed:absolute;top=" & TopY & ";left=" & LeftX & ";}'>" & TeXt & "</div>" & horizontalline(TopY + 7, LeftX - LeftIncrement + 3, LeftX + 3)
End Function

Private Function Initialise(FileName As String)
    ' Initalizing variables
    FName = FileName   ' The FileName
    LeftX = 10               ' Left Margin. Change this to change the left margin
    TopY = 10                ' Top Margin. Change this to change the top margin
    totalHTML = "<font face='courier new'><html xmlns:v='urn:schemas-microsoft-com:vml'><head> <style> v\:* { behavior: url(#default#VML); } </style> </head><pre>"  ' Html to Initialise XML VML stuff
End Function