linq query with multiple search options

http://www.henrycordes.nl/post/2009/06/multiple-search-criteria-searching-using-linq-to-sql.aspx

:  /// <summary>

   2:  /// Gets a LINQ to SQL Query according the provided parameters

   3:  /// </summary>

   4:  /// <param name="postsQuery"></param>

   5:  /// <param name="title"></param>

   6:  /// <param name="tags"></param>

   7:  /// <param name="createdOn"></param>

   8:  /// <param name="bodyText"></param>

   9:  /// <returns></returns>

  10:  private IQueryable<Post> GetPostsQuery(IQueryable<Post> postsQuery,

  11:                                         string title,

  12:                                         string tags,

  13:                                         string bodyText,

  14:                                         DateTime? createdOn)

  15:  {

  16:      if (!string.IsNullOrEmpty(title))

  17:          postsQuery = postsQuery.Where(p => p.Title.Contains(title));

  18:   

  19:      if (!string.IsNullOrEmpty(tags))

  20:          postsQuery = postsQuery.Where(p => p.Tags.Contains(tags));

  21:   

  22:      if (!string.IsNullOrEmpty(bodyText))

  23:          postsQuery = postsQuery.Where(p => p.Body.Contains(bodyText));

  24:   

  25:      if (createdOn.HasValue && createdOn.Value > DateTime.MinValue)

  26:          postsQuery = postsQuery.Where(p => p.CreatedOn.Value.Date == createdOn.Value.Date);

  27:   

  28:      return postsQuery;

  29:  }

Listing 4: IQueryable<Post> GetPostsQuery, extends and returns the IQueryable<Post> query

Listing 5 contains the method GetpostsPagingQuery. This method also extends and returns the query. LINQ to SQL provides paging with the Skip (skip all rows untill) and Take (take n number of rows) methods. And this method uses these methods to extends the query with paging capabilities.

   1:  private IQueryable<Post> GetPostsPagingQuery(IQueryable<Post> postsQuery,

   2:                                         int? startRow,

   3:                                         int? rowCount)

   4:  {

   5:      if ((startRow.HasValue) && (rowCount.HasValue && rowCount.Value > 0))

   6:          postsQuery = postsQuery.Skip((int)startRow).Take((int)rowCount);

   7:   

   8:      return postsQuery;

   9:  }

Listing 5: Adds paging to query, using Skip and Take methods