通过类访问dbconfig文件 - PHP

Question

I would like to insert data to the database for which I have a class called InsertTodb. But I am unable to access $dbc variable (which is in dbconfig .php) through class. Here is the code

My Class File

<?php
require("dbconfig.php");
class InsertTodb {
    public $tableNme;
    public $data1;
    public $data2;
    public $data3;
    public $arg1;
    public $arg2;
    public $arg3;


    function insertData($tableName, $data1, $data2, $data3, $val1, $val2, $val3) {
        $this->tableNme = $tableName;       
        $this->data1 = $data1;
        $this->data2 = $data2;
        $this->data3 = $data3;
        $this->arg1 = $val1;        
        $this->arg2 = $val2;        
        $this->arg3 = $val3;        

        $insquery = "insert into ".$this->tableNme."(".$this->data1.", ".$this->data2.", ".$this->data3.") values('".$this->arg1."', '".$this->arg2."',' ".$this->arg3."')";
        echo $insquery; 

        if(mysqli_query($dbc, $insquery)) {                 
        $success = "Product added successfully."; 
        echo $success; 
        }
        else {
        $failed = "Error adding product."; 
        echo $failed; 
        }
}
}
?>

My dbconfig file

<?php
$db_hostname = 'localhost';
$db_username = 'root';
$db_password = '';
$db_name = 'oop';

$dbc1 = mysqli_connect ($db_hostname,$db_username, $db_password,$db_name);

if (mysqli_connect_errno()) {
echo "Could not establish database connection!";
exit();
}
?>

My code

<?php

include "InsertTOdb.php";

$ins = new InsertTodb();

$ins->insertData("tableone", "name", "age", "desig",  "Guru", "25", "Accountant");

?>

When I run the above program, it shows the error "Notice: Undefined variable: dbc" and ..." Warning: mysqli_query() expects parameter 1 to be mysqli, null given in ...". I am new to OOP. Please help to fix it.

Answer 1

You should refactor your code a little. First of all,

<?php
include "dbconfig.php"; // Add this first.
include "InsertTOdb.php";
$ins = new InsertTodb($dbc1); // Feed the connector to your class.
$ins->insertData("tableone", "name", "age", "desig",  "Guru", "25", "Accountant");
?>

Now change the InsertTOdb class a little:

class InsertTodb {
    private $dbc;
    public function __construct($dbc) {
        $this->dbc = $dbc;
    }

    // ... the rest of class's properties ...
    function insertData($tableName, $data1, $data2, $data3, $val1, $val2, $val3) {
        ...
        // Change $dbc to $this->dbc.
        if(mysqli_query($this->dbc, $insquery)) {
            ...
        }
        ...
    }
    ...
}

Your insertData() looks a bit clunky with all these $data1, $data2 etc. values (you should pass them all at once as arrays or objects), but this should be enough for now.