How to output HTML Agility Pack for WP7

Question

I have the below code to parse an section of an html page.

What I would like to know is how to output it to either a listbox or text box.

Whenever I try I get unhandled exceltion error

private void PhoneApplicationPage_Loaded(object sender, RoutedEventArgs e) {

var doc = new HtmlDocument();
doc.LoadHtml("http://www.sourceURL.com");

var node = doc.DocumentNode.Descendants("div").FirstOrDefault(x => x.Id == "FlightInfo_FlightInfoUpdatePanel");

 var value = node.InnerHtml;
 this.textBox1.Text = value;

Exception error is :

System.NullReferenceException was unhandled
Message: NullReferenceException

Stack trace is:

   at Auckland_Airport.MainPage.PhoneApplicationPage_Loaded(Object sender, RoutedEventArgs e)
   at MS.Internal.CoreInvokeHandler.InvokeEventHandler(Int32 typeIndex, Delegate handlerDelegate, Object sender, Object args)
   at MS.Internal.JoltHelper.FireEvent(IntPtr unmanagedObj, IntPtr unmanagedObjArgs, Int32 argsTypeIndex, String eventName)

HTML Layout is

        <div id="FlightInfo_FlightInfoUpdatePanel">

        <table cellspacing="0" cellpadding="0"><tbody>
            <tr class=""><td class="airline"><img src="/images/airline logos/US.gif" title="US AIRWAYS. " alt="US AIRWAYS. " /></td><td class="flight">US5316</td><td class="codeshare">NZ46</td><td class="origin">Rarotonga</td><td class="date">02 Sep</td><td class="time">10:30</td><td class="est">21:30</td><td class="status">CHECK IN CLOSING</td></tr><tr class="alt"><td class="airline"><img src="/images/airline logos/NZ.gif" title="AIR NEW ZEALAND LIMITED. " alt="AIR NEW ZEALAND LIMITED. " /></td><td class="flight">NZ6</td><td class="codeshare">&nbsp;</td><td class="origin">Los Angeles</td><td class="date">02 Sep</td><td class="time">19:15</td><td class="est">19:15</td><td class="status">DEPARTED</td></tr><tr class=""><td class="airline"><img src="/images/airline logos/AC.gif" title="Air Canada. " alt="Air Canada. " /></td><td class="flight">AC6093</td><td class="codeshare">NZ6</td><td class="origin">Los Angeles</td><td class="date">02 Sep</td><td class="time">19:15</td><td class="est">19:15</td><td class="status">DEPARTED</td></tr><tr class="alt"><td class="airline"><img src="/images/airline  class="d
    </div>
</div>

Clearer HTML

<div id="FlightInfo_FlightInfoUpdatePanel">

   <table cellspacing="0" cellpadding="0"><tbody>
     <tr class="">
     <td class="airline"><img src="/images/airline logos/NZ.gif" title="AIR NEW ZEALAND LIMITED. " alt="AIR NEW ZEALAND LIMITED. " /></td>
     <td class="flight">NZ8</td>
     <td class="codeshare">&nbsp;</td>
     <td class="origin">San Francisco</td>
     <td class="date">01 Sep</td>
     <td class="time">17:15</td>
     <td class="est">18:00</td>
     <td class="status">DEPARTED</td>
     </tr>
     <tr class="alt">
     <td class="airline"><img src="/images/airline logos/AC.gif" title="Air Canada. " alt="Air Canada. " /></td>
     <td class="flight">AC6103</td>
     <td class="codeshare">NZ8</td>
     <td class="origin">San Francisco</td>
     <td class="date">01 Sep</td>
     <td class="time">17:15</td>
     <td class="est">18:00</td>

Is there a div with id="DivName" in your markup? Can't see any from the snippet you posted. — Darin Dimitrov
@Darin Sorry, just edited. I am just trying to start simple and display all the html in the FlightInfo_FlightInfoUpdatePanel div and then I will parse the individual td's. I just can't get it to output. — Rhys
At what point do you get an exception. Maybe the stack trace you have added is not complete. — Maxim V. Pavlov
@Rhys, is the exception thrown because the div is not found, or it is thrown when you try to assign the value to the textbox? — Darin Dimitrov
@maxim It build fine, but when I try and run on the emulator it gets the exceptiomn and highlights var value = node.InnerHtml; — Rhys

Maxim V. Pavlov Maxim V. Pavlov · Accepted Answer · 2011-09-02T09:02:08

HtmlDocument.Load function doesn't take a Uri as a paramter, it should recieve a structured HTML, that you have somehow retrieved from a server.

Here is the code for your case using the WebClient class to retrieve the HTML from server:

        WebClient client = new WebClient();
        client.DownloadStringCompleted += new DownloadStringCompletedEventHandler(client_DownloadStringCompleted);

        client.DownloadStringAsync(new Uri(@"http://www.aucklandairport.co.nz/en/FlightInformation/DomesticArrivalsAndDepartures.aspx"));

    }

    void client_DownloadStringCompleted(object sender, DownloadStringCompletedEventArgs e)
    {
        var html = e.Result;

        var doc = new HtmlDocument();
            doc.LoadHtml(html);

        var list = doc.DocumentNode.Descendants("div").ToList();

        var node = doc.DocumentNode.Descendants("div").FirstOrDefault(x => x.Id == "FlightInfo_FlightInfoUpdatePanel");

        var value = string.Empty;

        if (node != null)
            value = node.InnerHtml;
    }

At the end, the value variable holds the inner HTML you need to further parse.

How to output HTML Agility Pack for WP7

1 Answers