Question

I have an MVC app. At a particular point I manually added an error to the ModelState.

ModelState.AddModelError("duplicateInvoiceNumberOrganisation", "The combination of organisation and invoice number must be unique");

What I’m wanting to know is how later from the controller do I get the value of error.

I know I can get to the ModelStateValues by:

controller.ModelState.Values

and it’s in there because it says:

Count = 1
    [0]: {System.Web.Mvc.ModelState}

But how do I actually get the "The combination of organisation and invoice number must be unique" out of it?

Answer 1

string error = ModelState["duplicateInvoiceNumberOrganisation"]
    .Errors[0]
    .ErrorMessage;

or to the get the first error of the first modelstate item that has errors associated with it:

string error = ModelState
    .Where(x => x.Value.Errors.Count > 0)
    .First()
    .Value
    .Errors[0]
    .ErrorMessage;