Angular 6/PHP Http failure during parsing for - php

Question

I am currently learning angular 6 and have problems with my connection to the database.
addData(nachname: any, vorname: any, telefon: any) {
return this.client.post('http://localhost/api/add.php', {
nachname,
vorname,
telefon
}).subscribe((data) => {
console.log(data);
});
}
<?php
header("Access-Control-Allow-Credentials: true");
header('Content-type: application/json');
header("Access-Control-Allow-Origin: ".((isset($_SERVER['HTTP_ORIGIN'])) ?
$_SERVER['HTTP_ORIGIN'] : "*"));
header('Access-Control-Allow-Headers: X-Requested-With, content-type,
access-control-allow-origin, access-control-allow-methods, access-control-
allow-headers');
$db = mysqli_connect("localhost", "root", "", "telefonauskunft");
if(!$db){
exit("Verbindungsfehler: ".mysqli_connect_error());
}
$db -> set_charset('utf8');
$model = json_decode(file_get_contents("php://input"));
$sql = "Insert Into telefonauskunft ('Nachname', 'Vorname', 'Telefon')
Values ('$model -> Nachname', '$model -> Vorname', '$model ->
Telefon');";
if($model->Nachname){
$qry = $db->query($sql);
}
$db->close();
?>
These are my codes. I got a normal select query with this.client.get (...).
Unfortunately I get with this code
error
:
{error: SyntaxError: Unexpected token < in JSON at position 0 at JSON.parse () at XMLHttp…,
Http failure during parsing for
Where is my problem? I thank you in advance for answers and help

Answer 1

You should print something out in your PHP file, for instance a boolean value stating that the database query was successful. Ideally, you should follow common JSON API guidelines, cf. http://jsonapi.org/format/upcoming/
print json_encode($db->query($sql));