Author: Richard Waddell Created: 5/5/2011 12:17 PM RssIcon
Richard Waddell - All About LightSwitch
By Richard Waddell on 12/3/2011 8:22 AM
 

Many-to-Many Relationships A typical validation task that involves a many-to-many relationship involves a User who can update a number of Entities and an Entity that can be updated by a number of Users. For instance a School Book Inventory system where the counts for books at a particular school can only be updated by an employee of that school. Each employee can update a number of counts and each count can be updated by a number of employees. The application must prevent unauthorized data base updates and prevent employees from seeing counts from other schools.

We’ll start with validation. Although this article touches on validation on both client and server, to really understand what’s going on I suggest you see this post by Prem Ramanathan and this article he wrote for Code magazine....
By Richard Waddell on 6/14/2011 10:17 AM
The default Add and Edit screens generated by LightSwitch often don’t allow the control you need to meet the business requirements.  Consider the scenario where an entity must have a password column.  Ideally we’d want the ‘Add’ screen to look something like this:

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The default Add and Edit screens are inadequate for two reasons.

No masked password text box A second password text box is required for matching, requiring a property that doesn’t...
By Richard Waddell on 5/21/2011 8:29 AM
 

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LightSwitch removes so much tedium from programming that I’m hoping it can be integrated into any Silverlight application. Obviously that requires Custom Controls, so the focus becomes finding the best patterns for interaction between LightSwitch and Custom Controls.

My first goal was to incorporate drag and drop. I spent a lot of time trying to come up with scenarios that were not trivial but also wouldn’t take a long time to set up. But I kept running into a fuzzy area when I tried to think about...
By Richard Waddell on 5/5/2011 5:40 PM
Often we don’t care who the logged-in User is because we can control what they can do through Roles and Permissions. But if the User is a member of some group, it would be handy to place the Users table in a many-to-one relationship with that group. In this example the groups are SalesTeams made up of SalesPersons. All Sales made by a particular team are accessible only by members of that team.

To make that happen a new User is created, if necessary, when a SalesPerson is created. Since a SalesPerson is in a many-to-one relationship with SalesTeam, so is the User. This article shows you how to create the UserRegistration and then two ways to identify the SalesPerson associated with the logged-in User and thereby the relationship with SalesTeam and Sales.

Start by adding a SalesTeam entity:

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