$_POST doesn't work with my form - php

Question

Now i made a simple form with 2 input one for name and one for button
i want in php file echo name input
<form action="del.php">
<input type="text" name="name" />
<input type="submit" name="btn" value="button"/>
</form>
in del.php
<?php
session_start();
$_SESSION['name'] = $_POST['name'];
echo "".$_POST['name']."";
giving me white screen when every time
i want to echo any thing that typed in this input

Answer 1

You are missing method attribute in your form.
<form action="del.php" method="POST">
<input type="text" name="name" />
<input type="submit" name="btn" value="button"/>
</form>
The method attribute specifies how to send form-data (the form-data is sent to the page specified in the action attribute).
The form-data can be sent as URL variables (with method="get") or as HTTP post transaction (with method="post").
Source: https://www.w3schools.com/tags/att_form_method.asp

Answer 2

the default method when a form is submitted is GET, you need to specify the POST method (method="post") in your <form> tag:
<form action="del.php" method="post">

Answer 3

Your form is not POSTing its GETing (see the url params which will be set example.com?name=) this is because you not set the from method for POST:
<form action="del.php" method="post">
<input type="text" name="name" />
<input type="submit" name="btn" value="button"/>
</form>
And within your PHP you should check its post and check that the values are set:
<?php
session_start();
if ($_SERVER['REQUEST_METHOD'] == 'POST') {
$name = isset($_POST['name']) ? $_POST['name'] : null;
// set your session - not sure you need this :/
$_SESSION['name'] = $name;
// echo out your result but also protect from XSS by using htmlentities
echo htmlentities($name);
}