Consuming the Windows Live Search Webservice using ASP.NET and AJAX 1.0

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Introduction

This application will bind search results from the Windows Live Search Webservice to a GridView control and make use of AJAX 1.0 for searching and paging. This application allows you to search multiple websites at once. A practical example can be found here. The city example, however, isn't AJAX-driven like the example in this article.

You can customize the search properties via the web.config file. Please have the following requirements met before proceeding.

1. ASP.NET 2.0 installed.
2. Setup the downloaded app in IIS, and choose ASP.NET 2.0.
3. Have AJAX 1.0 installed on your machine.
4. Obtain a Key from MS to use this Webservice (MSN). You can then add the key to the app setting in web.config.

Background

I found bits and pieces of random examples on the net but nothing substantially helpful. I thought this might be helpful for folks who wish to see a working example. You can always take out the AJAX and capture the search query via a querystring, with just a few minor changes.

Using the code

The WindowsLiveSearch class has one main method called Search. Instantiating the class will fill the required properties from web.config to use in the Search method.

The main configuration properties are organized as a type called LiveSearchProperties.

/// <summary>
/// Properties used for setting up web service
/// </summary>

public class LiveSearchProperties
{
    private string _searchLic;
    public string SearchLic
    {
        get { return _searchLic; }
        set { _searchLic = value; }
    }

    private int _resultsSize;
    public int ResultsSize
    {
        get { return _resultsSize; }
        set { _resultsSize = value; }
    }

    private string _searchSites;
    public string SearchSites
    {
        get { return _searchSites; }
        set { _searchSites = value; }
    }

    private SafeSearchOptions _searchOptions;
    public SafeSearchOptions SearchOptions
    {
        get { return _searchOptions; }
        set { _searchOptions = value; }
    }
}

In the constructor, the properties are filled. SP is the local property of WindowsLiveSearch of type LiveSearchProperties. Here, the configuration settings are stored in a new instance of LiveSearchProperties and then stored in SP (the WindowsLiveSearch property).

/// <summary>
/// Creates a WindowsLiveSearch and fills properties with values
/// </summary>

public WindowsLiveSearch()
{
    // -------------------------------

    // Initialize properties

    // -------------------------------


    // Error Property

    ErrorMsg = "";
    // LiveSearchProperties

    LiveSearchProperties sp = new LiveSearchProperties();
    sp.SearchLic = ConfigurationManager.AppSettings["SearchLic"];
    sp.ResultsSize = Int32.Parse(ConfigurationManager.AppSettings["ResultsSize"]);
    sp.SearchSites = ConfigurationManager.AppSettings["SearchSites"];
    sp.SearchOptions = SafeSearchOptions.Off;
    SP = sp; // Save instance to class property

    sp = null; // Null out unused object

}

The Search method is as follows:

/// <summary>  
/// This is the main function you call after object creation. 
/// You can pass the search query in here and get a list of 
/// results to work with. You can easily bind these results to an 
/// ASP.NET control if desired or foreach the list to get the data.
/// </summary>

/// <param name="searchQuery">The search query</param>

/// <returns>A generic list of search results</returns>

public IList<LiveSearchResults> Search(string searchQuery)
{
    // Basic checks

    if ((searchQuery == null) ||
        (searchQuery.Length == 0) ||
        (searchQuery.Trim() == ""))
        return null;

    IList<LiveSearchResults> resultsCollection = 
              new List<LiveSearchResults>();
    using (MSNSearchService s = new MSNSearchService())
    {
        SearchRequest searchRequest = new SearchRequest();
        searchRequest = SetUpRequest(searchRequest, searchQuery, SP);
        SearchResponse searchResponse;
        try
        {
            searchResponse = s.Search(searchRequest);
            resultsCollection = CaptureResults(searchResponse);
        }
        catch (Exception e)
        {
            ErrorMsg = e.ToString();
        }
        finally
        {
          // If there was an error

          if (ErrorMsg.Length > 0)
            LogMessage("There was an error with searchQuery: " +
              searchQuery);
          else
            LogMessage("A successful search was made with searchQuery: " +
              searchQuery);
        }
    }
    return resultsCollection;
}

The Search method uses the MSNSearchService class, which utilizes two main classes: SearchRequest and SearchResponse. The SearchRequest object consists of all the properties needed to allow the Search class to understand what type of search you are trying to make. In this example, we are going to do a web search.

The following is the SearchRequest method:

/// <summary>  
/// Sets up the MSN SearchRequest Object
/// </summary>

/// <param name="searchRequest">A SearchRequest Object</param>
/// <param name="searchQuery">The search query</param>
/// <param name="sp">LiveSearchProperties Object</param>

/// <returns>The SearchRequest Object</returns>

private SearchRequest SetUpRequest(
    SearchRequest searchRequest,
    string searchQuery,
    LiveSearchProperties sp)
{
   SourceRequest[] sr = new SourceRequest[1];
   sr[0] = new SourceRequest();
   sr[0].Source = SourceType.Web;
   sr[0].ResultFields = ResultFieldMask.All;
   sr[0].Count = sp.ResultsSize;
   sr[0].Offset = 0;

   searchRequest.Requests = sr;

   searchRequest.Query = searchQuery + " " + sp.SearchSites;
   searchRequest.SafeSearch = sp.SearchOptions;
   searchRequest.AppID = sp.SearchLic;
   searchRequest.Flags = SearchFlags.MarkQueryWords;
   searchRequest.CultureInfo = "en-US";
   return searchRequest;
}

After you setup the Request, you can use the Webservice to get a SearchResponse. I created a method called CaptureResults to do this. To store the captured results, I created a type called LiveSearchResults.

The LiveSearchResults properties:

/// <summary>
/// Properties used to store search results
/// </summary>

public class LiveSearchResults
{
   private string _url;
   public string URL
   {
       get { return _url; }
       set { _url = value; }
   }

   private string _title;
   public string Title
   {
       get { return _title; }
       set { _title = value; }
   }

   private string _description;
   public string Description
   {
       get { return _description; }
       set { _description = value; }
   }

   private string _displayURL;
   public string DisplayURL
   {
       get { return _displayURL; }
       set { _displayURL = value; }
   }

   private string _cachedURL;
   public string CachedURL
   {
       get { return _cachedURL; }
       set { _cachedURL = value; }
   }
}

This is the CaptureResults method:

/// <summary>
/// Creates a list of Search Results
/// </summary>

/// <param name="search_Response">The LiveSearch Response</param>

/// <returns>A collection of search results</returns>

private IList<LiveSearchResults> CaptureResults(SearchResponse search_Response)
{
 // Create a collection object to build list

 IList<LiveSearchResults> resultsCollector = new List<LiveSearchResults>();
 //Get data from web service

 foreach (SourceResponse response in search_Response.Responses)
 {
   Result[] response_results = null;
   response_results = response.Results;
   //Secure and store output

   foreach (Result response_result in response_results)
   {
      LiveSearchResults row = new LiveSearchResults();
      row.URL = AntiXss.HtmlEncode(CheckForNull(response_result.Url));
      row.Title = AntiXss.HtmlEncode(CheckForNull(response_result.Title))
          .Replace("&#57344;", "<strong>").Replace("&#57345;", "</strong>");
      row.Description = AntiXss.HtmlEncode(CheckForNull(response_result.Description))
          .Replace("&#57344;", "<strong>").Replace("&#57345;", "</strong>");
      row.DisplayURL = AntiXss.HtmlEncode(CheckForNull(response_result.DisplayUrl))
          .Replace("&#57344;", "<strong>").Replace("&#57345;", "</strong>");
      row.CachedURL = AntiXss.HtmlEncode(CheckForNull(response_result.CacheUrl));
      resultsCollector.Add(row);
   }
 }
 return resultsCollector;
}

This method uses the AntiXssLibrary.dll from MS. This will prevent unwanted cross-site scripting data from getting stored in the results. This method builds and returns a generic list to the Search method, which will enable you to bind the results to a Web Control.

The Presentation layer

The ObjectDataSource does all the work.

<asp:ObjectDataSource ID="ObjectDataSource1" runat="server" SelectMethod="Search"
 TypeName="Windows.Live.Search.WindowsLiveSearch" OnSelected="ObjectDataSource1_Selected">
 <SelectParameters>
   <asp:FormParameter FormField="searchBox" Name="searchQuery" Type="String" />
 </SelectParameters>
</asp:ObjectDataSource>

As shown, you can see that I included the class in the TypeName parameter. I then selected the method "Search" from the class.

The OnSelected event is used to get the total results count. This was the only way I knew how to accomplish this, considering the GridView Count property only gives the count of the results actually shown on the screen.

The OnSelected method:

// Get the total number of records

protected void ObjectDataSource1_Selected(object sender, 
               ObjectDataSourceStatusEventArgs e)
{
  Instructionlbl.Text = "";

  try
  {
    IList<LiveSearchResults> resultsCollection = 
             new List<LiveSearchResults>();
    resultsCollection = (IList<LiveSearchResults>)e.ReturnValue;
    resultsTotal = resultsCollection.Count;
    if (resultsTotal == 0)
      Instructionlbl.Text = "Your search provided no results.";
  }
  catch (System.NullReferenceException)
  {
    Instructionlbl.Text = "Please enter a search term.";
  }
}

If the search query is blank, then there will be a System.NullReferenceException. So, that is where the Instruction Label comes in to ask the user to "Please enter a search term".

AJAX stuff

To get this to work, you must surround the controls you want updated in an AJAX UpdatePanel. In this example, I put the GridView control and the Instruction Label in the UpdatePanel.

To trigger the update panel, you simply supply the following:

<Triggers>
  <asp:AsyncPostBackTrigger ControlID="SearchButton" EventName="click" />
</Triggers>

This simply states to trigger the update panel when a Click event occurs.

Points of interest

Everything you need will be in the project download. You should be able to take what I did and customize it to your needs. You can play around with the Search settings in the web.config file. You can also change the default sites to search. All the settings are the same as if you were doing an advanced search with the Live Search Engine.

History

• 11/13/2007
• Added project to The Code Project.
• 11/20/2007
• Added logging (Optional feature in web.config)
• Fixed Field Null Reference Error
• Added search
• Provided a No Results message