Creating and Using External Lists in SharePoint 2010

This example illustrates how to create a Business Connectivity Services (BCS) with an external content type using Visual Studio and utilize this content type in a SharePoint external list.

Feature Overview

An external list is a list based on data from an external system outside of SharePoint such as a CRM system or relational database.

Task 1: Create a new Business Data Catalog Model project.

1. Open Visual Studio 2010 from the Start | Programs | Visual Studio 2010 menu.

2. Create a new project by using File | New Project.

3. Pick the SharePoint | 2010 templates.

4. From the SharePoint | 2010 templates select the Business Data Connectivity Model template.

5. Use BCSExample as the name.

6. Set the location to be C:\SPHOLs.

7. Press OK to create the project.

8. On the SharePoint Customization Wizard dialog, type the address of the site you want to deploy to, and select to deploy this as a farm solution.

9. Click Finish to proceed.

Task 2: Extend the custom entity to allow updating.

1. Click on the Entity1 | Methods area in the designer.

2. This brings up the BDC Method Details window for Entity1.

3. At the bottom of this window (you may need to scroll) find the Add a Method area.

4. Open the combo box on the Add a Method area and select Create Updater Method.

5. Select the newly created method called Update to retrieve the properties pane. Change Is Static = True.

Task 3: Add the code to store list data in an in memory collection.

1. Right click on Update and select View Code.

2. Add the following variable to the Entity1Service class;

static Dictionary<string, string> EntityCollection = new Dictionary<string, string>();

This variable will be used to hold the lists state information. A real world application would use a durable system such as a relational database instead.

3. Replace the existing method implementations with the following code:

public Entity1Service()

{

if (EntityCollection.Count == 0)

{

// Create some test list items.

Entity1 e1 = new Entity1();

e1.Identifier1 = "e1";

e1.Message = "e1 Item Data";

EntityCollection.Add(e1.Identifier1, e1.Message);

Entity1 e2 = new Entity1();

e2.Identifier1 = "e2";

e2.Message = "e2 Item Data";

EntityCollection.Add(e2.Identifier1, e2.Message);

}

}

public static Entity1 GetEntityById(string id)

{

// Looks up the Entity information based on the id passed

Entity1 entity1 = new Entity1();

entity1.Identifier1 = id;

entity1.Message = EntityCollection[id];

return entity1;

}

public static IEnumerable FindAllEntities()

{

// Iterates through our backing

List entities = new List();

foreach (String key in EntityCollection.Keys)

{

Entity1 entity1 = new Entity1();

entity1.Identifier1 = key;

entity1.Message = EntityCollection[key];

entities.Add(entity1);

}

return entities;

}

public static void Update(Entity1 inParameter1)

{

// Updates the corresponding item in the collection

EntityCollection[inParameter1.Identifier1] = inParameter1.Message;

}

Task 4: Deploy and create an entity backed list based on this example.

1. Right click on the BusinessDataCatalog1 project and select deploy.

2. In the web browser click Site Actions -> View All Site Content -> Create.

3. Beneath Custom Lists click External List.

4. Specify CustomList as the name of the new list. Beneath Entity Type click the browse icon. Select the newly created Business Data Type in the list and click OK.

The list will render the sample list items we added in the entity’s constructor.

Selecting an item and pressing edit allows changing of the field which in turn calls the Update method we defined in the custom entity.