I searched over the web and I found that a lot of people say that server-side script is better when making a contact form for a website... Can someone tell me why, please?
In my little experience I appreciate when a contact form is able to hightlight istantly when I wrote a wrong email, or a field is missing, rather than waiting for the answer of the server after processing the input in a php page. Maybe is better to implement both jquery validating and server-side validating?
They must be talking about the form validation. Client side validation is usually done with JavaScript/jQuery which can be easily manipulated using tools like Firebug. If user disables his JavaScript, the validation will fail and wrong data will be posted, inorder to prevent that, Server Side Validation is used for example, PHP, ASP.
The data is posted to the server, server validates the data, if it's incorrect, it will throw back the error to the user, and the most important is that server side validation cannot be manipulated/modified easily.
Now you may ask why to validate Client Side if it can be modified/broken easily? Well, not everyone is intelligent to fool your validation, home/normal users often forget some fields to fill up which are compulsory, if you do not keep a client side check at all, your server will get more and more requests directly, thus increasing the load, inorder to prevent that, you need to keep a client side check as well, which will prevent the form details to be posted to the server directly, thus decreasing the server load.
Also, it will save the time for your users, JavaScript validations are very quick, the users are responded with the related error messages when they are typing, or they move to the next field or very soon after the submit button is pressed. Where as server validation will make the process lengthy as forms will be submitted first, server will validate, and than it will return the message. Not much friendly for an user huh?
So the bottom line is validate both, Client Side and Server Side, but make sure you DO VALIDATE Server Side.
If you use client side languges like javascript or jquery for validation then modern browsers have the option to turn off or disable javscript and if they do so then validations will not work.But its not applicable in the case of server side validations.You can refer these links for more
http://www.dzyngiri.com/client-side-vs-server-side-validation/
You can perform sending and validating on server side but you can also provide basic validation on client side. Thanks to that you can notify user when something is wrong instantly. But also you will be sure that all data is correct (because of server side validation).
