isset() function always returns true [closed] - php

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I've been figuring out how to do this but it seems not to be working.
My code for the form:
<form name="register" method="POST" action="php\reg.php">
<label>Email:</label>
<input type="email" name="email"/>
.
.
.
</form>
Code for the "reg.php" file:
if (isset($_POST['email'])) {
echo "success!";
} else {
echo "empty!";
}
?>
Problem is, whenever I input or not in the email textbox, isset function always returns the true value. how can I resolve this??

Answer 1

All answers that tell you about using isset() and empty() to check form values are... bad. Use one of the filter functions to check if a POST/GET/COOKIE variable is present and validate or sanitize it. Here is an example:
$email = filter_input(INPUT_POST, "email", FILTER_VALIDATE_EMAIL);
if ($email === NULL) {
die("Email field not present in form");
} elseif ($email === FALSE) {
die("Email is present but its value is invalid");
}
Note: the empty() function has a gotcha and I would not recommend using it for form validation unless you understand exactly what it does: it returns true for all falsy values. This means 0 is considered empty which is often an acceptable value in certain cases. Example (bad one):
if (empty($_POST["number_of_children"])) {
// triggers even when user enters 0
die("number of children field is empty");
}

Answer 2

isset() checks if the values is set, so it's true even if the value is empty string. Use empty():
if (empty($_POST['email']) == false) {
echo "success!";
}else{
echo "empty!";
}

Answer 3

<?php
if (!empty($_POST['email'])) {
echo "success!";
}else{
echo "empty!";
}
?>

Answer 4

try this-
<?php
if (!empty($_POST['email'])) {
echo "success!";
}else{
echo "empty!";
}
?>

Answer 5

Null and/or empty strings are still set if the variable is declared.
$_POST contains empty string for your value, and isset() returns true. Use empty() or add != '' in your if condition.try this:
if (!empty($_POST['email']))

Answer 6

Try to use empty() function to check if there is anything in email filed of $_POST array.
The example code based on your code is below:
<?php
if (isset($_POST['email']) && !empty($_POST['email'])) {
echo "success!";
} else {
echo "empty!";
}
?>

Answer 7

<?php
if (isset($_POST['email']) && $_POST['email'] != "") {
echo "success!";
}else{
echo "empty!";
}
?>
try this way