Validations In ASP.NET MVC 5.0: Part 13

“ClientSideValidation” is my model class, I need to resolve it form the “using MVCValidationsDemo.Models; namespace.



After this, now I need to add a view, right click near action method and add a view.



View name should be Index, Template name should be “Create” and model class should be ClientSideValidation
(MVCValidationDemo.Models)”.

Check the “Reference script libraries” and “Use a layout page” because application automatically adds these references.

Click on “Add” button.



Now client side validation is ready for use, save your application and run the project by pressing F5 key.

Call the respective controller that is “ClientSide”.



Name field is valid, Address field is empty and email is not valid in the following screenshot.



In the following screenshot Address and Email are valid but name field is required.



If all fields are valid then there is no validation message.



Server Side Validation

Now, I’m going to use Server Side Validation in ASP.NET MVC using the Data Annotation API.

Server side validations ensure that the received data is correct and valid. If the received data is valid then we do further processing with the data. Server side validations are very important before playing with sensitive information of a user.

Server-side validation must be done whether we validate the received data on the client side. User could disable script in his browser or do something else to bypass client-side validation. In this case server-side validation must require to protect our data from dirty input.

In the ServerSideValidation named Model class, I have taken four properties, instead of three, rename the Model class and Controller to “ServerSideValidation” named:



Now, I’m going to make some changes in the Controller, my controller is ServerSideController.



In the following code I have used [HttpPost]action method so that the method handles only HTTP POST requests.

I am using if (string.IsNullOrEmpty(model.Name)) to check if there name is empty, then message will be shown on the view whenever the data is not to be validated in the model, same for the other properties.

For the Email property I have used regular expression validation, if email does not not match with the expression it simply fire a validation that Email is not valid, otherwise enter valid email, if email format will be right then validation does not occur.

“Regx” is the class that will be resolved by “using System.Text.RegularExpressions;” namespace.
See the following screenshot:


Now, I need to add a view, right click on near action method and add a view.



View name should be Index, Template name should be “Create” and model class should be ServerSideValidation (MVCValidationDemo.Models)”.

Check the “Reference script libraries” and “Use a layout page” because application automatically adds these references.

Click on to “Add” button.



Now client side validation is ready for use, save your application and run the project by pressing F5 key.

Call the respective controller that is “ServerSide”. All fields are empty; you can check it one by one.



Click on to “Create” button, you will find all validations are working. Here's the screenshot: