&& isset and number of fields in PHP - php

Question

The following PHP is used to send an email from a contact form. My question is:
Now I have 3 fields, name, email and message and in the PHP there is:
if(isset($_POST['name'])
&& isset($_POST['email'])
&& isset($_POST['message'])
&& isset($_POST['token'])){
If I wanted to add anther field, do I also need to add && isset for it?
What are && isset? are they really needed?
Here is the PHP:
<?php
session_start();
if ($_SERVER['REQUEST_METHOD'] == 'POST'){
ob_start();
if(isset($_POST['name'])
&& isset($_POST['email'])
&& isset($_POST['message'])
&& isset($_POST['token'])){
if($_SESSION['token'] != $_POST['token']){
$response = "0";
} else {
$_SESSION['token'] = "";
$name = $_POST['name'];
$email = $_POST['email'];
$message = $_POST['message'];
$to = "email here";
$subject = "New Message From: $name";
$message = "Name: $name<br/>
Email: $email<br/>
Message: $message";
$headers = 'MIME-Version: 1.0' . "\r\n";
$headers .= 'Content-type: text/html; charset=utf-8' . "\r\n";
$headers .= 'From: '.$email . "\r\n";
$mailed = ( mail($to, $subject, $message, $headers) );
if( isset($_POST['ajax']))$response = ($mailed) ? "1" :
"0"; else $response = ($mailed) ? "<h2>Success!</h2>" :
"<h2>Error! There was a problem with sending.</h2>";
echo $response;
}
} else {
echo "Form data error!";
}
ob_flush();
die();
}
?>
DO I need them if I have a JS validation script?

Answer 1

You could simply make use of the comma operator , with the isset for checking multiple fields !
So you don't need to add the isset keyword again and again.
The code...
if(isset($_POST['name'],$_POST['email'],$_POST['message'],$_POST['token']))
{
echo "All the fields are set and good to go !";
}
else
{
echo "Some fields were not filled !";
}

Answer 2

You need to learn the basics in PHP
isset() is a, lets say little helping "function", you can check, it the field "is set", whether it is "filled" or not.
And && is a logical operator.
If you have another field and don't exactly now, what you are doing, then yes, just add && and isset, but I can only give you an advice: Learn PHP and try to understand it - it not hard.
Actually I know some very good tutorials in German language, but I am sure some fellow "overflowers" can recommend you some.
If the you like the tutorials, then buy a book - I know, they often are very expensive - but it is worth it!
Happy Coding!

Answer 3

&& is a logical operator.
&& isset is not function. only isset is a language construct which checks a session variable or post variable is set.For adding another variable also you need to use && isset($_POST['variable'])
if(isset($_POST['name'])
&& isset($_POST['email'])
&& isset($_POST['message'])
&& isset($_POST['token'])){
this statement means that it is checking whether post variables name,email,message,token were set and loop goes in if all values were set.because && allows only if all conditions return true

Answer 4

If tests the condition, if it is true, the following block (code between { and } ) is executed.
&& is the and operator, isset tests whether the variable is set.
if(isset($_POST['name'])
&& isset($_POST['email'])
&& isset($_POST['message'])
&& isset($_POST['token'])){
In plain english this reads: if variable $_POST['name'] is set and variable $_POST['email'] is set as well and ... (you got it). You can actually replace && with and.
Isset also accepts multiple arguments, so you can indeed do isset($_POST['name'],$_POST['email',...).
A previous answer talks about comma operator, there is a comma operator, but this is not it, this is a function having many arguments.
$_POST['name'] in plain english is the 'name' input field in the form that has been posted.
Note that isset-check of the fields does not make much sense here. They can be set allrigt, but still be empty. If you want to make the fields mandatory you should test both that they are set and not empty.
if(isset($_POST['name']) and !empty($_POST['name'])...
! is the logical not operation, so !empty means not empty.
Whether the new field should be tested like this, depends on whether it is mandatory or not.
Reading a PHP-tutorial might do you very good.

Answer 5

Here, if you want to send the value of a new field by mail, you'll always need to test the existence of it by isset.
Also, I suggest you to test if the variable is not empty, because fields like 'input text' will always exist even if it is empty.
You can use empty function to test if it exists and not empty
if(!empty($_POST['name'])
&& !empty($_POST['email'])
&& !empty($_POST['message'])
&& !empty($_POST['token'])){
//...
}