Dhananjay Kumar

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.

We will see ,

1. How to insert an item in SharePoint list using SPLinq

2. How to update an item in SharePoint list using SPLinq

3. How to delete an item in SharePoint list using SPLinq

4. How to fetch items from SharePoint list using SPLinq.

Advantage

1. SPLinq supports visual studio intellisense

2. SPLinq provides strong typecasting and data typing

3. SPLinq works without CAML query.

4. Using SPLinq , existing knowledge of LINQ could be apply to SharePoint development .

5. SPLinq provides completely language dependent development of SharePoint

6. Multiple list item insertion and deletion can be performed very easily with one syntax.

7. Join operation can be performed very easily on the related list

Using CAML when performing operation against SharePoint list was biggest challenge. CAML does not provide developer friendly syntaxes. SPLinq helps us to get rid of CAML.

SPLinq can be used with

1. Managed application , like windows or console or WPF

2. With SharePoint client object models.

3. With SharePoint webparts.

4. With SPGridView.

Challenge

The main challenge working with SPLInq is creation of entity class on command prompt. SPMetal creates a partial Entity class to apply Linq against that.

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,

Step1

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

Step2

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

Step3

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

Step4

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.

Step5

Add the namespace

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

Now console application project is ready for the CRUD operation on SharePoint 2010 list using SPLinq

Fetch the items from list using SPLinq

a. First we need to create instance of ProductContext class

Here we need to provide URL of the SharePoint site as parameter to constructor.

b. Now we can apply simple LINQ to access the list, like below.

c. There is one more way to access the list

Code for fetching list items

ProductDataContext context = new ProductDataContext("<a href="http://dhananjay-pc/my/personal/Test1">http://dhananjay-pc/my/personal/Test1</a>");
 var result = from r in context.Test1_Product select r;
 foreach (var r in result)
 {
 Console.WriteLine(r.ProductId + ":" + r.ProductName + ":" + r.ProductPrice);
 }
 Console.ReadKey(true);

Output

Insert to SharePoint list using SPLinq

1. Create the instance of Data Context

2. Get the entity list where item would get inserted

3. Create instance of List item to be inserted

4. Call the InsertOnsubmit on the instance of Entity list.

5. Call sumitchange on the context

Code for inserting a list item

ProductDataContext context = new ProductDataContext("<a href="http://dhananjay-pc/my/personal/Test1">http://dhananjay-pc/my/personal/Test1</a>");
 EntityList<Test1_ProductItem> products = context.GetList<Test1_ProductItem>("Test1_Product");
 Test1_ProductItem itemToInsert = new Test1_ProductItem()
 {
 ProductId = "9",
 ProductName = "Soccer Ball",
 ProductPrice = 600
 };
 products.InsertOnSubmit(itemToInsert);
 context.SubmitChanges();

Update a Particular list item in SharePoint list

1. Create instance of Data Context

2. Fetch the list item to be updated using SPLInq

3. Modify the list item property wished to be updated. I am updating Product name to Dhananjay of Product Id 1

4. Call the submit change on the context

Code for updating a list item

ProductDataContext context = new ProductDataContext("<a href="http://dhananjay-pc/my/personal/Test1">http://dhananjay-pc/my/personal/Test1</a>");
 var itemToUpdate = (from r in context.Test1_Product where r.ProductId == "1" select r).First();
 itemToUpdate.ProductName = "Dhananjay";
 context.SubmitChanges();

Delete a Particular item from the list

1. Create the instance of Data Context

2. Get the entity list where item would get inserted

3. Fetch the list item to be deleted using SPLInq

4. Call deleteonsubmit to delete a particular item from SharePoint list

5. Call the submit change on the context

Code for deleting a list item

ProductDataContext context = new ProductDataContext("<a href="http://dhananjay-pc/my/personal/Test1">http://dhananjay-pc/my/personal/Test1</a>");
 EntityList<Test1_ProductItem> products = context.GetList<Test1_ProductItem>("Test1_Product");
 var itemToDelete = (from r in context.Test1_Product where r.ProductId == "1" select r).First();
 products.DeleteOnSubmit(itemToDelete);
 context.SubmitChanges();