LINQ to SharePoint: SPLinq in SharePoint 2010

Objective 

In this article, we will see how to work with LINQ to SharePoint.   I have tried to address all the common errors we encounter when first time we start using LINQ against SharePoint.

Assumption 

We have a custom list 

1. Name of the list is Test_Product. 
2. Columns of  the list is as below
   
   
   
   
3. There are two items in the list 
   
   
   
   
4. URL of the SharePoint  site is    
   
   "http://dhananjay-pc/my/personal/Test1

Now we need to fetch the list items in a managed console application using Linq to Sharepoint or SPLinq. 

Follow the below steps, 

Step 1 

Open the command prompt and change directory to 

C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\14\BIN

Type command CD C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\14\BIN

 

Step 2

Now we need to create the class for corresponding list definitions. 

C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\14\BIN> spme

tal.exe /web:http://dhananjay-pc/my/personal/Test1 /namespace:nwind /code:Product.cs

In above command we are passing few parameters to spmetal.exe, they are as below 

1. /web:Url    
   
   Here we need to provide URL of SharePoint site 
   
   /web:http://dhananjay-pc/my/personal/Test1 /
   
   ://dhananjay-pc/my/personal/Test1 / is  URL of SharePoint site, I created for myself. You need to provide your SharePoint site URL here.
   
   
2. /namespace:nwind
   
   This would be the namespace under which class of the list will get created. In my case name of the namespace would be nwind.
   
   
3. /code:Product.cs
   
   This is the file name of the generated class.  Since we are giving name Product for the file then class generated will be ProductDataContext

Step 3

Open visual studio and create a new project of type console.  Right click on the Project and select Properties

 

Click on the Build tab and change Platform Target to Any CPU.

 

Click on the Application tab and change the Target framework type to .Net Framework 3.5.

 

Step 4

 

The class we created in Step2 will by default get saved in the same folder with SPMetal.exe. So to see where the class got created we need to navigate to folder C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\14\BIN

Add created class to the Project 

Now add this class to the project. To do this, right click on the project and select Add existing item.  Then browse to above path and select Product.cs

 

Add references to the Project 

Microsoft.SharePoint 

Microsoft.SharePoint.Linq 

Right click on Reference and select Add Reference. To locate Microsoft.SharePoint and Microsoft.SharePoint.Linq dll browse to C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\14\ISAPI. All the SharePoint dll are here in this location. 

Step 5

Add the namespace 

 

Nwind is the name of the namespace of the class we created in Step2. 

Step 6

Now we will write the code to access the SharePoint list using Linq to SharePoint. 

1. First we need to create instance of ProductContext class 
   
   
   
   Here we need to provide URL of the SharePoint site as parameter to constructor. 
2. Now we can apply simple LINQ to access the list, like below.
   
   
   
   
3. There is one more way to access the list 
   
   
   

Program.cs

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using Microsoft.SharePoint.Client;

using Microsoft.SharePoint.Linq;

using Microsoft.SharePoint;

using nwind;

namespace SPLinqTest1

{

    class Program

    {

        static void Main(string[] args)

        {

            ProductDataContext context = new ProductDataContext("http://dhananjay-pc/my/personal/Test1");

            //EntityList<Test1_ProductItem> products = context.GetList<Test1_ProductItem>("Test1_Product");

            var res = from r in context.Test1_Product   select r;

            foreach (var r in res)

            {

                Console.WriteLine(r.ProductId + ":" + r.ProductName + ":" + r.ProductPrice);

            }

            Console.ReadKey(true);

        }

    }

}

Output