ASP.NET Core 3 and React

Adding validation to posting a question

We can add validation to a model by adding validation attributes to properties in the model that specify rules that should be adhered to. Let's add validation to the request for posting a question:

1. Open QuestionPostRequest.cs and add the following using statement:

using System.ComponentModel.DataAnnotations;

This namespace gives us access to the validation attributes.

2. Add a Required attribute just above the Title property:

[Required]public string Title { get; set; }

The Required attribute will check that the Title property is not an empty string or null.

3. Before we try this out, put a breakpoint on the first statement within the PostQuestion action method in QuestionsController.cs.
4. Let's run the ...