How do I make a website field mandatory?

There is no way within standard HTML code to make a field mandatory because it does no evaluation. For this you need JavaScript or, more robustly, PHP.

First, it is a good idea in your HTML to say which fields are mandatory or not, for instance by marking them with a '*' by them.

Then you do the check in your PHP code after the form has been submitted. So let's say we have a field called 'mandatory' and the form was submitted by post, here is how we can check for a value:


<?php

$anyvalue = $_POST[mandatory];

if(!$anyvalue) { echo "No value - please go back and fill in"; }

//don't use if you want '0' to be a valid value



//a better test for the variable to have some contents



$length = strlen($anyvalue);

if(!$length) { echo "No value - please go back and fill in!"; }

?>

Comments on this Question/Answer

Can anyone please tell me the script I need to make the "name/nickname" field mandatory?
By: Sylvia Lisi, 06 Aug 2009 12:04:49

Reply to comments / post your own comment >>>

ASK A QUESTION

More forms PHP Questions

How can I access information sent through POST on a form?

I have a form that I need to do two things: send all the input values to a confirmation/pay page, and send to me via email. Payment is based on what the customer picks (naturally). The way I have it set up is the form action goes to the confirmat

how to display like table from database records?

hello I found this code somewhere and tried to create online dictionary with it. I managed to insert the code in to my template index.php. But after the user click submit button the result shows in other blank self created page something like index.php?a

i just wanted to put a textbox beside the query of the evaluation form. how can i do that? ========================== here is my php form index.php PERFORMANCE APPRAISAL INSTRUMENT var Event = { add: function(obj,type,fn) {