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Let’s create a Full Name calculated field in the Employees controller. This field will display a concatenation of First Name and Last Name field values.

Start the Project Designer. In the Project Explorer, switch to the Controllers tab. Right-click on Employees / Fields node, and press New Field.

Give this field the following settings:

Press OK to save the field.

In the Project Explorer, drag Employees / Fields / FullName (String(80), read-only) field node and drop it onto Employees / Views / createForm1 to create a data field.

Right-click on Employees / Fields / FullName (String(80), read-only) node, and press Add SQL Converter.

Double-click on Employees / Fields / FullName node.

Change the Context Fields property:

Press OK to save the field. Double-click on Employees / Business Rules / FullName_Converter – Calculate|Insert|Update (Sql / Before) - r100 node.

Replace the default script with the following:

if @FirstName is not null and @LastName is not null
begin
    set @FullName = @FirstName + ' ' + @LastName
end

Press OK to save the business rule. On the Project Designer toolbar, press Browse.

Navigate to the Employees page, and create a new employee. Enter values in First Name and Last Name fields.

When the user shifts focus away from the field, Full Name will be calculated.

The Items Data Controller property allows the population of lookup values from another controller in the web app.

For example, suppose that you have configured the static lookup items for Reorder Level field in the Products table of Northwind database.

Providing a list of static lookup items offers many advantages, such as limiting user input while providing a clear list of options.

The functionality can be extended by creating a table to store these values externally. This will allow user management of lookup items.

Creating the Reorder Level Table

Start SQL Server Management Studio. In the Object Explorer, right-click on Databases / Northwind / Database Diagrams, and press New Database Diagram.

If prompted to create support objects required to use database diagramming, press Yes.

When the Add Table window appears, select Products table and press Add. Then press Close.

Right-click on white space and press New Table.

Enter the name of “ReorderLevels” for the table and press OK.

Give this table the following columns:

Save the diagram.

In the Object Explorer, right-click on Databases / Tables / dbo.ReorderLevel node, and press Edit Top 200 Rows.

Insert the following rows:

Go back to the database diagram. Drag ReorderLevelNumber column from ReorderLevel table onto ReorderLevel column in Products table.

Confirm that the right fields are configured and press OK twice to save the foreign key relationship.

Finally, add the controller to the project by refreshing the project settings with ReorderLevel table selected.

Configuring the Lookup

Start the Project Designer. In the Project Explorer, expand Products / Fields /  ReorderLevel field n0de. Highlight all items underneath the field node, right-click, and press Delete.

Double-click on Products / Fields / ReorderLevel node.

Change the Items Data Controller in order to populate the dropdown with data from the selected controller:

Press OK to save. On the toolbar, press Browse.

Navigate to the Products page, and edit a record. The Re0rder Level field will be populated with values from the ReorderLevel controller.

Values can be added, edited, or deleted by navigating to the Reorder Level page.

Note that using Drop Down List is not the most efficient way to render a lookup – the client library will populate the drop down when the form is initialized. If the controller has a lot of data, it may impact the database server. It would be more advisable to use Auto Complete or Lookup style.