Several questions

Several questions

• Spock101

  What is the most correct solution depends a bit on how large your XML file is. If it is not too large I would choose to work with the XmlDocument class and use XPath expression to extract the nodes that are interesting.

  I made a sample project that is just a standard windows application with 2 comboboxes and a button. I added a XML file to the project that looks like this

  < xml version="1.0" encoding="utf-8" >
<data>
<comboBox1>
<item text="Item1.1"/>
<item text="Item1.2"/>
<item text="Item1.3"/>
</comboBox1>
<comboBox2>
<item text="Item2.1"/>
<item text="Item2.2"/>
<item text="Item2.3"/>
</comboBox2>
</data>


  This is the code in the form.

  Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim xmlDoc As System.Xml.XmlDocument
xmlDoc = New System.Xml.XmlDocument
' Default run in projectdir\bin\Debug|Release
' and the xml file is in the projectdir
xmlDoc.Load("..\..\Data.xml")

Dim xmlNodes As System.Xml.XmlNodeList
Dim xmlNode As System.Xml.XmlNode

xmlNodes = xmlDoc.SelectNodes("/data/comboBox1/item/@text")
For Each xmlNode In xmlNodes
ComboBox1.Items.Add(xmlNode.Value.ToString())
Next

xmlNodes = xmlDoc.SelectNodes("/data/comboBox2/item/@text")
For Each xmlNode In xmlNodes
ComboBox2.Items.Add(xmlNode.Value.ToString())
Next
End Sub


  As you can see I load the whole xml document in the xmlDoc.Load(). I can then select multiple nodes using a xpath expression with the SelectNodes method. This will give me XmlNodeList that is a collection of XmlNode objects

  If you are reading the values from a very large xml document you should use an event driven parsing. The XmlDocument loads everything into memory and can use up too much resources to be efficient.

  
  
  

• Ripon12

  Thanks for the help. I have yet to try that method, but I plan to. The XML file is pretty small, so that shouldn't be a problem. I do have one question. I saw something similar to this earlier and wondered what the @ sign in a line like this means:

  xmlDoc.SelectNodes(/data/comboBox2/item/@text)

  Does that mean you're referring to an attribute If I'm not going to refer to an attribute in the XML file, do I leave that out Thanks.

  
  

• bdubyah

  I get a "The remote server returned an error: (407) Proxy Authentication Required."  error message at the following line:

  xmldocument.Load("http://xoap.weather.com/weather/local/49707 cc=*&dayf=5")

   

  Any ideas

  
  

• Robert Dunlop

  You are correct the @ sign means I am looking for a attribute named "text" in the element named "item".

  If you would just like to get the element named "item" the xpath would look like this "/data/comboBox2/item" and the value of the node would be the text inside the element.

  
  
  

• mclagett

  Thanks. :) Rather than posting the whole code for this here, I put it as a page on my website since it's long. You can look at it at http://blakenet.myftp.org/weathercode.doc. Are we able to include images in these posts I can't see how to do it if we are. Anyway, you can see a screenshot of the app on my home page at http://blakenet.myftp.org. This is the first VB program I wrote. I added more features to it lately. It now has a feature that lets you select which US zip code you want to see the weather for when the app starts and also lets you select a "Balloon zip code", which is displayed in a tooltip icon when you hover over the icon in the system tray. This lets you keep the app minimized and still check the weather. I originally only had the ability to let the user save three zip codes, but I learned more and now it's unlimited. Hope you enjoy it. If you live in the US (or know US zip codes, you can get the zip file for the program at http://blakenet.myftp.org/X-Weather.zip. I'm not sure, but I think that build is the latest one. If it shows a screen making you sign up for a license key, let me know and I'll put up the latest build.
  

• ANDERSLIND

  Hmm, that's odd, because that URL works for me.
  

• g.neeraj

  If you're talking about the weather URL, here's the code I have to show the current weather on my form. You can probably see what changes you need to make for it to work for you. This is for a specific form with labels and images.

  Public Sub GetWeather(ByVal myzip As String)

  Try

  CurrentConditionsLabel.Text = ""

  'Current Weather

  Dim xmldocument As New System.Xml.XmlDocument

  xmldocument = New System.Xml.XmlDocument

  xmldocument.Load("http://xoap.weather.com/weather/local/" + myzip + " cc=*&dayf=5")

  Dim Xnodes As System.Xml.XmlNodeList

  Dim Xnode As System.Xml.XmlNode

  Xname = xmldocument.SelectSingleNode("/weather/loc/dnam").InnerText

  Wlocation.Text = Xname

  Wlocation2.Text = Xname

  Xnode = xmldocument.SelectSingleNode("/weather/cc")

  Xnodes = Xnode.ChildNodes

  For Each Xnode In Xnodes

  If Xnode.Name = "tmp" Then

  CurrentTemp.Text = Xnode.InnerText() + Chr(186)

  ElseIf Xnode.Name = "flik" Then

  CurrentConditionsLabel.Text = CurrentConditionsLabel.Text + "Feels Like: " + Xnode.InnerText() + Chr(186) + Environment.NewLine

  ElseIf Xnode.Name = "t" Then

  PicCondition.Text = Xnode.InnerText()

  ElseIf Xnode.Name = "icon" Then

  WeatherStatus.Image = Image.FromFile("icons/" & Xnode.InnerText() & ".jpg")

  ElseIf Xnode.Name = "wind" Then

  Dim XWindList As System.Xml.XmlNodeList

  Dim Xwind As System.Xml.XmlNode

  Xwind = Xnode.SelectSingleNode("/weather/cc/wind")

  XWindList = Xwind.ChildNodes

  'Dim Windstring As String = Nothing

  Dim WindGust As String

  Dim WindSpeed As String

  For Each Xwind In XWindList

  If Xwind.Name = "t" Then

  Dim WindDir As String = "Wind: From " + Xwind.InnerText

  If WindGust = "N/A" Then

  CurrentConditionsLabel.Text = CurrentConditionsLabel.Text + WindDir + WindSpeed

  Else

  CurrentConditionsLabel.Text = CurrentConditionsLabel.Text + WindDir + WindSpeed + " Gusting to " + WindGust + " MPH"

  End If

  ElseIf Xwind.Name = "s" Then

  WindSpeed = " at " + Xwind.InnerText + " MPH"

  'Windstring = Windstring + "at " + Xwind.InnerText + " MPH"

  ElseIf Xwind.Name = "gust" Then

  WindGust = Xwind.InnerText

  'CurrentConditionsLabel.Text = CurrentConditionsLabel.Text + Windstring

  End If

  Next

  End If

  Next

  GetForecast(myzip)

  Catch ex As Exception

  MessageBox.Show("Sorry, we've encountered an error. For debugging purposes (AKA telling Blake), here's the error: " + ex.Message)

  End Try

  End Sub

  
  

• Thomas Kristensen

  It is enough to write it like "/weather/loc/dname" but if you want to be sure that it is of a certain weather "ver" or loc "id" you can write it like this

  "/weather[@ver='2.0']/loc[@id='ZIP goes here']/dnam"

  The value of the node will be "City Name is Here"

   

  
  
  

• dale_barr

  Blake81 wrote:

  Hmm, that's odd, because that URL works for me.

  Works for me too! I like this one. How about posting the code for GetForecast(myzip) I have played around with RSS feeds off and on and the Weather forecasts are the most fun.

  james

  aka:Trucker

  
  

• ThankYouDriveThrough

  I've figured out part of my answer.  Here's the code.

  Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

  Dim xmlFile As String = "C:\Documents and Settings\Owner\Desktop\weather.xml"

  Dim xmlTr As New XmlTextReader(xmlFile)

  While xmlTr.Read

  If xmlTr.Name = "dnam" AndAlso xmlTr.NodeType = XmlNodeType.Element Then

  ListBox1.Items.Add(xmlTr.ReadString)

  ElseIf xmlTr.Name = "t" Then

  ListBox1.Items.Add(xmlTr.ReadString)

  ElseIf xmlTr.Name = "flik" Then

  ListBox1.Items.Add(xmlTr.ReadString)

  ElseIf xmlTr.Name = "s" Then

  ListBox1.Items.Add(xmlTr.ReadString)

  End If

  End While

  xmlTr.Close()

  End Sub

  Now I need to figure out how to specify which information I want when some of the tag names are used more than once.  Sorry to make this long, but I want to post some XML to show.  I just don't know how to specify a certain parent/child relationship, since I figure that's how it's done. Notice how "t" is used under cc and wind (and also other places).  How would I specify if I only wanted "t" if it were under wind for example   Thanks

  - <cc>

    <lsup>2/21/06 11:25 AM EST</lsup>

    <obst>Oil City, PA</obst>

    <tmp>28</tmp>

    <flik>17</flik>

    <t>Cloudy</t>

    <icon>26</icon>

  - <bar>

    <r>30.03</r>

    <d>rising</d>

    </bar>

  - <wind>

    <s>16</s>

    <gust>20</gust>

    <d>240</d>

    <t>WSW</t>

    </wind>

   

  
  

• Der M

  How can I retrieve the data from the link in the first post in this thread so that I can display it on a form I am just looking for the code to retrieve the xml data from a URL. If someone can post a snippet I would be very greatful. Thanks...
  

• Matt Palmerlee

  Another quick newbie question. Here's a shortened version of the XML file.

  < xml version="1.0" encoding="ISO-8859-1" >

  - <!--

  This document is intended only for use by authorized licensees of The Weather Channel. Unauthorized use is prohibited. Copyright 1995-2005, The Weather Channel Interactive, Inc. All Rights Reserved.

  -->

  - <weather ver="2.0">

  - <head>

  <locale>en_US</locale>

  <form>MEDIUM</form>

  <ut>F</ut>

  <ud>mi</ud>

  <us>mph</us>

  <up>in</up>

  <ur>in</ur>

  </head>

  - <loc id="ZIP goes here">

  <dnam>City Name is Here</dnam>

  <tm>5:10 PM</tm>

  <lat>33.58</lat>

  <lon>-85.1</lon>

  <sunr>7:18 AM</sunr>

  <suns>6:30 PM</suns>

  <zone>-5</zone>

  </loc>

  What would the XPath be if I wanted to get the data stored in <dnam> I wasn't sure if I should include the <weather ver="2.0"> or not in the XPath. Thanks.

  
  

• gbm1

  Thanks, I will give your code a try...
  

• Mange

  If I enter that exact URL into Internet Explorer the data comes up fine, but for some reason it doesn't work in VB, it just gives me that error...
  
• Several questions