Linq Filter by adding Where Clause

  187         public IQueryable<Talent> GetTalents(string searchExpression)

  188         {

  189             IQueryable<Talent> t;

  190             if (string.IsNullOrEmpty(searchExpression))

  191             {

  192                 t = _repository.GetTalents();

  193             } 

  194             else

  195             {

  196                 t = BasicSearch(searchExpression);

  197             }

  198             return t;

  199         }

  200

  201         private static readonly char[] SplitDelimiters = " ".ToCharArray();

  202

  203         // search should come in as  'jon johnny323@yahoo.com rodgers'

  204         private IQueryable<Talent> BasicSearch(string search)

  205         {

  206             // Just replacing "  " with " " wouldn't help with "a      b"

  207             string[] terms = search.Trim()

  208                                    .ToLower()

  209                                    .Split(SplitDelimiters,

  210                                           StringSplitOptions.RemoveEmptyEntries);

  211             IQueryable<Talent> talents = _repository.GetTalents();

  212             foreach (string s in terms)

  213             {

  214                 talents = AddBasicSearch(talents, s);

  215             }

  216             return talents;

  217         }

  218

  219         private IQueryable<Talent> AddBasicSearch(IQueryable<Talent> t, string s)

  220         {

  221             return t.Where(x =>  x.FirstName.ToLower().Contains(s)

  222                     || x.LastName.ToLower().Contains(s) 

  223                     || x.Email.ToLower().Contains(s) 

  224                     || x.LanguagesString.ToLower().Contains(s) 

  225                     );

  226         }

Linq to Lambda

I changed a Linq expression to a Lambda expression so I could refactor the filter. Here is the before and after

Before: (Linq expression)

results = from u in ctx.ActiveUsers

          where (u.CompanyID != 1 &&

                   (u.LastName.ToLower().Contains(searchString)

                   || u.Email.ToLower().Contains(searchString)

                   || u.Company.Name.ToLower().Contains(searchString)))

          orderby u.LastName, u.FirstName

          select new Employee

          {

              ID = u.ID,

              FirstName = u.FirstName,

              LastName = u.LastName,

              Email = u.Email,

              CompanyName = u.Company.Name,

              CompanyID = u.CompanyID.ToString()

          };

After: (Lambda expression)

results = ctx.ActiveUsers

    .Where(Employee.GetExpression(searchString))

    .OrderBy(u =>  u.LastName ).ThenBy(u => u.FirstName)

    .Select(u => new Employee {
      ID = u.ID

      , FirstName = u.FirstName
      , LastName = u.LastName

      , Email = u.Email
      , CompanyName = u.Company.Name

      , CompanyID = u.CompanyID.ToString() });

plus this to keep the where expression the same on the count:

private static Expression<Func<User, bool>> GetExpression(string searchString)

{ 

    Expression<Func<User, bool>> p = (u => u.CompanyID != 1 &&

                       (u.LastName.ToLower().Contains(searchString)

                       || u.Email.ToLower().Contains(searchString)

                       || u.Company.Name.ToLower().Contains(searchString)));

    return p;

}

so that GetExpression can be used here to make sure that our count query is the same as the select

public static int GetCustomerCount()

{

    UserContext ctx = new UserContext();

    int totalRecords;

    string searchString = SearchString; 

    totalRecords = ctx.ActiveUsers.Count(Employee.GetExpression(searchString));

    return totalRecords;

}

Linqpad

Linqpad is a nice way to learn how to write linq statements. There is no install required. Check it out here. Thanks Joseph

asp.net handlers serving xml

your handler code

namespace XXXX.TourAdmin.Web.Admin

{

    /// 

    /// Summary description for $codebehindclassname$

    /// 

    [WebService(Namespace = "http://tempuri.org/")]

    [WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]

    public class VideoHandler : IHttpHandler

    {

        public void ProcessRequest(HttpContext context)

        {

            //context.Response.ContentType = "text/plain";

            context.Response.ContentType = "UTF-8";

            context.Response.Write(this.GetVideoXml());

        }

        protected string GetVideoXml()

        {

            VideoContext vc = new VideoContext();

            var videos = from v in vc.Videos

                         select new 

                         {

                             VideoClip = v.FileLocation,

                             Title = v.Title,

                             Date = v.VideoDate,

                         };

            XDocument xmlDoc = new XDocument();

            XElement xEleVideos = new XElement("videos");

            xmlDoc.Add(xEleVideos); 

            foreach (var v in videos)

            {

                xEleVideos.Add(new XElement("video",  new XAttribute("VideoClip", v.VideoClip),

                    new XAttribute("Title", v.Title), new XAttribute("Copy", v.Date)));

            }

            string s = xmlDoc.ToString();

            return s;

        }

        public bool IsReusable

        {

            get

            {

                return false;

            }

        }

    }

}

here is the data:

Title	FileLocation	VideoDate	active
Miami, Florida	20080914	2009-02-12 00:00:00	1

now put the url in the address bar
http://localhost/XXXX.TourAdmin.Web/Admin/VideoHandler.ashx

<videos>

  <video VideoClip="20080914" Title="Miami, Florida" copy="2009-02-12T00:00:00" />

<videos>

Props to Lewis

Linq to xml

Linq (Language Integrated Query) works on xml too

<content>

  <gallery Name="All Videos">

    <video VideoClip="20081014.flv" Title="Orlando, Florida" Copy="Feb 12, 2009"/>

    <video VideoClip="20081121.flv" Title="Atlanta, Georgia" Copy="Feb 12, 2009"/>

  </gallery>

</content>

protected void LoadGallaryList()

{

    string xmlFile = this.Server.MapPath("~/Flash/_xml/video.xml"); 

    XDocument xmlDoc = XDocument.Load(xmlFile); 

    var videos = from v in xmlDoc.Descendants("video") // .Elements("video")

                 select new 

                 {

                     VideoClip = v.Attribute("VideoClip").Value,

                     Title = v.Attribute("Title").Value,

                     Date = v.Attribute("Copy").Value,

                 }; 

    foreach (var v in videos)

    {

        lblCurrent.Text += "title:" + v.Title + " VideoClip:" + v.VideoClip + " Date:" + v.Date + "<br/>";

    }

}

output:
title:Orlando, Florida VideoClip:20080914.flv Date:Feb 12, 2009
title:Atlanta, Georgia VideoClip:20081121.flv Date:Feb 12, 2009