Unable to save form data to sql table using php - php

Question

I am trying to save a form data into sql table using php. Eventhough I am not getting error while submit, data is not showing up in table.
My submit button name is input_submit
Here is my code:
if(isset($_POST['input_submit'])){
include 'dbConnection.php';
include 'saveData.php';
}
dbConnection.php
<?php
$path = $_SERVER['DOCUMENT_ROOT'];
include_once $path . '/wp-load.php';
include_once $path . '/wp-config.php';
class ConnectDB{
private $servername;
private $username;
private $password;
private $dbname;
protected function connect(){
$this->servername ="localhost";
$this->username ="root";
$this->password ="";
$this->dbname ="testdb";
$conn = new mysqli($this->servername,$this->username,$this->password,$this->dbname);
if($conn -> connect_error) {
die("connection failed:".$conn-> connect_error);
}
return $conn;
}
}
?>
saveData.php:
<?php
class saveinput extends ConnectDB {
public function Savein(){
$date = $_POST['date'];
$entry_type = $_POST['entry_type'];
$amount = $_POST['amount'];
$sql = $conn->prepare("INSERT INTO wp_myexpenses (date, entry_type, amount)
VALUES(?, ?, ?)");
$sql->bind_param("sss",$date, $entry_type, $amount);
$sql->execute();
if ($sql->execute()) {
echo "success";
} else {
echo "failed";
}
}
}
?>
while submit, form is getting submitted. But when I check the db table, nothing is showing up. I am not understanding whats wrong here. Can someone guide me please.

Answer 1

You should call your "connect" method inside your Savein method in a var. So, your Savein method should be:
public function Savein(){
$conn = parent::connect(); // This is the only thing i've added
$date = $_POST['date'];
$entry_type = $_POST['entry_type'];
$amount = $_POST['amount'];
$sql = $conn->prepare("INSERT INTO wp_myexpenses (date, entry_type, amount)
VALUES(?, ?, ?)");
$sql->bind_param("sss",$date, $entry_type, $amount);
if ($sql->execute()) {
echo "success";
} else {
echo "failed";
}
}