Question

I’m implementing EF 5 in a winforms application and I’m persisting the context (DBContext) in a private field in the form.

I try to add an entity, and because it has some invalid properties, I get a DBEntityValidationException. Then, I set these properties to valid values and try to add it again, and I receive the exact same DBEntityValidationException.

I’m wondering if I need to clear anything? Here’s the code.

private SystemEntities _context = new SystemEntities(); // class field

try
{
    Customer customer = ... // set properties here
    _context.Customers.Add(customer);
    _context.SaveChanges();
}
catch (DBEntityValidationException ex)
{
    // get exception even though properties are updated with valid values
}

I do not observe this issue when updating an entity. Many thanks.

Answer 1

The comments pointed me to the right direction. Instead of trying to save the changes and catching the exception, I first get the validation results:

var results = new List<ValidationResults>();
Validator.TryValidateObject(entity, new ValidationContext(entity, null, null), results, true);

The problem was that it was actually adding the invalid entity to the set, so it kept throwing the exception on subsequent attempts. Thanks!