Asp.Net Core MVC Model Binding and Validation

Asp.Net Core MVC Model Binding and Validation

Model Binding in ASP.NET Core Model Validation in Asp.Net Core Model Validation Example in Asp.Net Core

Model Validation Example in Asp.Net Core

In the previous post we saw on how to perform form field validations using Model State, in this post we will see an example of using Model Validations in a MVC Form. Following is the Model class with the validations.

Model Validation in Asp.Net Core

Validation is an important part of any application which accepts inputs from users, the data entered by the user needs to be validated for integrity before it is saved in the database. Validations could be on the type of data like int, string, decimal etc. On the format of the data like email, SSN, Phone Number etc. Also we might need custom validation specific to the application.

Asp.Net Core MVC Model validation provides us an easy and effective way to validate user input, using Model validation we can specify the validation parameters in the Model object and the framework will take care of validating the inputs in the View.

Customize Validation error message in ASP.NET Core MVC

In the previous post we saw on how to implement field level validations by adding validation attributes to the Model class. We saw that the validation messages were auto generated based on the validation rules, we might want to add custom validation messages, we can do this by adding an ErrorMessage property to the validation attributes.

In the sample below we will add custom error messages using the ErrorMessage property and see how this is reflected in the View.

Adding Model Validations in ASP.NET Core MVC Views

In the previous posts we saw on how to create an Asp.Net Core MVC controller and views to View, Edit and Delete detail using Entity Framework Core. In this post we will see on how to add Model validations which will be applied to the Views to validate data before we Add/Delete details to the database.

Asp.Net Core makes it easy to validate entities, all we need to do is to add the validation properties to the Model class and Asp.Net Core takes care of applying the validations in the view automatically. In the previous version of Asp.Net MVC we had to validate the user input fields in the View layer using Validation controls like Required Field validator, Range Validator, Regular expression validator etc, but Asp.Net Core takes care of this for us.