Displaying error instead of null values in PHP - php

Question

I am building up a site in PHP which takes input of more than 20 fields from user. Hardly 3-4 field values are compulsory, rest can be left blank. I want to display a custom error message instead of blank or zero or null while displaying these values. How can this be done? I am using MySQL as backend.

Answer 1

I assume you use the $_POST array.
In that case you could just do:
$errors = array();
foreach($_POST AS $key => $value) {
if(empty($value)) {
$_POST[$key] = "Custom error message"; // Or place it in an apart array like:
$errors[$key] = "Custom error message";
}
}
You can also choose to print the message to the screen immediately. That's up to you.
Besides, did you ever consider a Validation library like:
http://kohanaframework.org/guide/security.validation
Good luck!

Answer 2

<?php
$var1 = 'Foo';
$var2 = '';
$var3 = NULL;
echo ( ! empty($var1)) ? $var1 : 'Not set!'; // Foo
echo ( ! empty($var2)) ? $var2 : 'Not set!'; // Not set!
echo ( ! empty($var3)) ? $var3 : 'Not set!'; // Not set!
/**
* Alternative function solution based on OP's comment:
*/
function output($str)
{
echo ( ! empty($str)) ? $str : 'Not set!';
return TRUE;
}
output($var1); // Foo
output($var2); // Not set!
output($var3); // Not set!