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Why is client-side validation not enough?
What is the purpose of using the both validations at the same time? Because it’s extra burden on the server for validating the form inputs in php if javascript validation is successful. Can not we use a flag and set or unset its value depending upon whether javascript validation is successful or not? And if the flag value is set, we will skip the php validation. Is it not possible? If it’s not possible can you explain with a valid real life example? Or can a user modify the value of the flag even if we pass it in header?
Waiting for some logical answers.
Thank you.
Validating with JavaScript saves you a trip to the server, and creates a nice responsive user experience.
Validating with PHP is necessary so you don’t get broken data, or worse (the user could disable JavaScript or post data to your PHP application in a number of ways).