What is validation?
Validation is a process of testing and ensuring that the user has entered required and properly formatted information through the web form.
What is Client-side validation?
In client-side validation method, all the input validations and error recovery process is carried out on the client side i.e on the user’s browser. It can be done using JavaScript, AJAX, HTML5 etc.
What is Server-side validation?
In server-side validation, all the input validations and error recovery process is carried out on the server side. It can be done using programming languages like C#.NET, VB.NET etc.
Differences and comparison:
Client-side validation is faster than server-side because, the validation takes place on client side (on browser) and the networking time from client to server is saved.
On the other hand, server-side validation is done on the web server. Then the server renders the data into html page and sends back to the client (browser).
Server-side validation is more secure than the client-side as the user cannot see the code even he does a view-source.
Conclusion:
Both the validation methods have their own significance. I would like to recommend that you should use both the validation methods Client-side validation to provide a better user experience and server-side to be sure that the input you get from client (browser) is actually validated and not just supposed to be validated by the client.
