How-to: Query Vista Search From Your App

Here are a few snippets of relevant source code from the demo:

public partial class Window1 : Window
 {
  private ImageCollection _foundImages = null;
  private string[] _exifProperties = new string[] {
   "System.Photo.CameraManufacturer", "System.Photo.CameraModel",
   "System.Photo.FNumber", "System.Photo.ExposureTime", "System.Photo.FocalLength",
   "System.Photo.ExposureBias", "System.Photo.MeteringMode",
   "System.Photo.ColorSpace"};

  private string[] _generalProperties = new string[] {
   "System.Author", "System.Keywords", "System.File.Description"};

  private void OnSearch(object sender, RoutedEventArgs e)
  {
   string indexerConnString = "provider=Search.CollatorDSO.1;EXTENDED PROPERTIES=\"Application=Windows\"";
   using (OleDbConnection conn = new OleDbConnection(indexerConnString))
   {
    conn.Open();
    string keywordValue = SearchBox.Text;

    _foundImages.Clear();
    GetImageFileResults(keywordValue, conn);
    ImageListBox.DataContext = _foundImages;
   }
  }

  private void GetImageFileResults(string keywordValue, OleDbConnection conn)
  {

   try
   {
    System.Collections.Hashtable checkNames = new System.Collections.Hashtable();

    string sqlString = "Select \"System.Title\", " +
        "\"System.DisplayFolder\", \"System.DisplayName\" " +
        "FROM systemindex..scope() " +
                    "WHERE FREETEXT(\"System.CanonicalType\", 'JPG') "/* +
                        "AND CONTAINS(\"System.Path\", 'file:')"*/;
                if (!string.IsNullOrEmpty(keywordValue))
                {
                    sqlString += " AND (\"System.Keywords\" = SOME ARRAY ['" + keywordValue + "'])";
                }

    OleDbCommand cmd = new OleDbCommand(sqlString, conn);

    using (OleDbDataReader reader = cmd.ExecuteReader())
    {

     while (reader.Read())
     {
      ImageInfo imageInfo = new ImageInfo();
      imageInfo.Title = reader.GetString(0);
                        string folder = reader.GetString(1);
                        string name = reader.GetString(2);
                        // workaround to ignore non-files
                        if (folder.Length < 2 || folder[1] != ':')
                            continue;
      imageInfo.ImagePath = System.IO.Path.Combine(
                            folder, name);
                        // Workaround to ignore peculiar files on non-existent
                        // volumes that build 5365 seems to return.
                        if (!System.IO.File.Exists(imageInfo.ImagePath))
                            continue;
                        if (imageInfo.ImagePath.Contains("Temporary Internet Files"))
                            continue;
      if (checkNames.ContainsKey(imageInfo.Title))
      {
       int index = (int)checkNames[(string)imageInfo.Title];

       if (_foundImages[index] != null)
       {
        if (_foundImages[index].Variations == null)
        {
         ImageCollection variationCollection = new ImageCollection();
         variationCollection.Add(imageInfo);
         _foundImages[index].Variations = variationCollection;
        }
        else
        {
         _foundImages[index].Variations.Add(imageInfo);
        }
       }

      }
      else
      {
       imageInfo.Variations = new ImageCollection();
       imageInfo.Variations.Add(imageInfo);
       int currentIndex = _foundImages.Count;
       checkNames.Add(imageInfo.Title, currentIndex);
       _foundImages.Add(imageInfo);

      }
     }

    }
   }
   catch (OleDbException)
   {
    // Not finding any results is ok.
   }