How do I check EntityValidationErrors when validation fails?

问题

I get this message when I try to edit a property in MVC 4 database first project. I'm using the MVC default edit page.

"Validation failed for one or more entities. See "EntityValidationErrors" property for more details."

Where do I check for validation?

回答1:

Go to your edit function, put a try - catch block and catch the exception - 'DbEntityValidationException'

if you want to see the errors, iterate though the validation errors.

here is a simple code example.

catch (DbEntityValidationException ex)
{
    foreach (var errors in ex.EntityValidationErrors)
    {
        foreach (var validationError in errors.ValidationErrors)
        {
             // get the error message 
            string errorMessage = validationError.ErrorMessage;
        }
    }
}

回答2:

If you set a break point in your controller you can check which values have errors against them by looking in the ModelState. The ModelState.Values collection contains the error and the key is the field.

来源：https://stackoverflow.com/questions/17020947/how-do-i-check-entityvalidationerrors-when-validation-fails