Visual Basic 2015 Unleashed

Custom Validations

Validating data is one of the most important activities in every data access system, so LINQ to SQL provides its own methodologies, too. To accomplish data validation, you can take advantage of partial methods. You might remember that in Chapter 20, “Advanced Language Features,” you got a practical example of partial methods when discussing LINQ to SQL. Validation rules are useful in LINQ to SQL for two main reasons: The first one is that they enable you to understand whether supplied data is compliant to your requirements; the second one is that they allow you to check whether supplied data has a SQL Server type counterpart. The following code example demonstrates both examples. Imagine you want to add a new product to the ...