I am new to the idea of oop php and i am trying to write an irc php.
What I'm trying to do:
I am trying to query my database, get results from my database and put it into an array inside my program.
I tried making a new function to carry out the task and called it in the __construct function.
I have shortened the code but it pretty much looks like this:
Any thoughts and ideas are much appreciated.
class IRCBot
{
public $array = array();
public $servername = "localhost";
public $username = "root";
public $password = "usbw";
public $dbname = "bot";
function __construct()
{
//create new instance of mysql connection
$conn = new mysqli($this->servername, $this->username, $this->password, $this->dbname);
if ($mysqli->connect_errno)
{
echo "Failed to connect to MySQL: (" . $mysqli->connect_errno . ") " . $mysqli->connect_error;
}
echo $mysqli->host_info . "\n";
$this->database_fetch();
}
function database_fetch()
{
$query = "SELECT word FROM timeoutwords";
$result = mysqli_query($query);
while($row = mysqli_fetch_assoc($result))
{
$array[] = $row();
}
}
function main()
{
print_r($array);
}
}
$bot = new IRCBot();
Changes
1) Change if ($mysqli->connect_errno) to if ($conn->connect_errno)
2) Change $array[] = $row(); to $array[] = $row;
3) Add return $array; in function database_fetch()
4) Call database_fetch() function inside main() function instead of constructor.
5) Add $this->conn in mysqli_query() (Thanks #devpro for pointing out.)
Updated Code
<?php
class IRCBot
{
public $array = array();
public $servername = "localhost";
public $username = "root";
public $password = "usbw";
public $dbname = "bot";
public $conn;
function __construct()
{
//create new instance of mysql connection
$this->conn = new mysqli($this->servername, $this->username, $this->password, $this->dbname);
if ($this->conn->connect_errno)
{
echo "Failed to connect to MySQL: (" . $this->conn->connect_errno . ") " . $this->conn->connect_error;
}
}
function database_fetch()
{
$query = "SELECT word FROM timeoutwords";
$result = mysqli_query($this->conn,$query);
while($row = mysqli_fetch_assoc($result)){
$array[] = $row;
}
return $array;
}
function main()
{
$data = $this->database_fetch();
print_r($data);
}
}
Quick Start
Object Oriented Programming in PHP
Classes and Objects
Principles Of Object Oriented Programming in PHP
First of all you need to fix error from your constructor, you can modify as:
function __construct()
{
//create new instance of mysql connection
$this->conn = new mysqli($this->servername, $this->username, $this->password, $this->dbname);
if ($this->conn->connect_errno)
{
echo "Failed to connect to MySQL: (" . $this->conn->connect_errno . ") " . $this->conn->connect_error;
}
echo $this->conn->host_info . "\n";
}
Here, you need to replace $mysqli with $conn because your link identifier is $conn not $mysqli
No need to call database_fetch() here.
You need to use $conn as a property.
Now you need to modify database_fetch() method as:
function database_fetch()
{
$query = "SELECT word FROM timeoutwords";
$result = mysqli_query($this->conn,$query);
$array = array();
while($row = mysqli_fetch_assoc($result))
{
$array[] = $row;
}
return $array;
}
Here, you need to pass add first param in mysqli_query() which should be link identifier / database connection.
Second, you need to use return for getting result from this function.
In last, you need to modify your main() method as:
function main()
{
$data = $this->database_fetch();
print_r($data);
}
Here, you need to call database_fetch() method here and than print the data where you need.
Related
I'm trying to get data from a table using a public function in PHP, but I get this error:
Uncaught Error: Call to a member function prepare() (PDO, php)
I'm searching for 2, 3 hours... But no result is similar or I did not understand.
<?php
class Config {
public static $SQL;
private function __construct() {
$host_name = "localhost";
$base_user = "root";
$base_pass = "";
$base_name = "home_page";
try {
self::$SQL = new PDO("mysql:host=$host_name;dbname=$base_name", $base_user, $base_pass);
self::$SQL->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
echo "Connected successfully";
} catch(PDOException $e) {
die("Something went wrong, database connection closed. Reason: ". $e->getMessage());
}
}
public static function GetData($table, $data, $id) {
$wc = Config::$SQL->prepare('SELECT `'.$data.'` FROM `'.$table.'` WHERE `ID` = ?');
$wc->execute(array($id));
$r_data = $wc->fetch();
return $r_data[$data];
}
}
?>
And I use this in my base file:
<h1><?php echo Config::GetData("page_details", "Moto", 1) ?></h1>
The error is from this line:
$wc = self::$SQL->prepare('SELECT `'.$data.'` FROM `'.$table.'` WHERE `ID` = ?');
Is there any particular reason why you want to use STATICeverywhere? The common approach is using public, dynamic methods and properties. I rewrote your sample with suggested naming convention in PHPs OOP, it works:
<?php
class Config
{
/** #var PDO $conn */
private $conn = null;
public function __construct()
{
$host_name = "localhost";
$base_user = "root";
$base_pass = "";
$base_name = "home_page";
try {
$this->conn = new PDO("mysql:host=$host_name;dbname=$base_name", $base_user, $base_pass);
$this->conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
echo "Connected successfully"; // <- this is unnnesesary
} catch (PDOException $e) {
die("Something went wrong, database connection closed. Reason: " . $e->getMessage());
}
}
public function findById($table, $data, $id)
{
$stmt = $this->conn->prepare('SELECT `' . $data . '` FROM `' . $table . '` WHERE `uid` = ?');
$stmt->execute(array($id));
return $stmt->fetch(PDO::FETCH_ASSOC);
}
}
// just for test
$cfg = new Config();
print_r($cfg->findById('foo', '*', 1));
or in your case
<?php echo $cfg->findById("page_details", "Moto", 1)['Moto'] ?>
I'm trying to connect using a simle db class. For some reason it only print out
"Initiate DB class"
test.php
include 'db.class.php';
echo 'Initiate DB class';
$db = new DB();
echo 'DB class did load';
db.class.php
class DB extends mysqli {
private static $instance = null;
private function __construct () {
parent::init();
$host = 'localhost';
$user = 'root';
$pass = 'MY_PASS';
$dbse = 'MY_DB';
parent::real_connect($host, $user, $pass, $dbse);
if (0 !== $this->connect_errno):
die('MySQL Error: '. mysqli_connect_error());
//throw new Exception('MySQL Error: '. mysqli_connect_error());
endif;
}
public function fetch ($sql, $id = null, $one = false) {
$retval = array();
if ($res = $this->query($sql)):
$index = 0;
while ($rs = $res->fetch_assoc()):
if ($one):
$retval = $rs; break;
else:
$retval[$id ? $rs[$id] : $index++] = $rs;
endif;
endwhile;
$res->close();
endif;
return $retval;
}
}
I have tried to search my log files for error but they come out empty.
Ok got it,
In your call to db your calling new DB(); which mean you're trying to call the constructor of your DB class.
In your DB class it looks like you're trying to create a singleton, but something is missing normally there would be something to assign the instance the database connection, and something that asks the instance if it's empty create a new connection or if it's not use the same instance.
At the end of the day to make this work you can change your constructor to public.
Try this:
Db_class:
class Db_class{
/***********************CONNECT TO DB*********************/
public function db_connect(){
$user = '***';
$db = '***';
$password = '***';
$host = '***';
try {
$dbh = new PDO("mysql:host=$host;dbname=$db", $user, $password);
}
catch(PDOException $err) {
echo "Error: ".$err->getMessage()."<br/>";
die();
}
return $dbh;
}
/******************PREPARE AND EXECUTE SQL STATEMENTS*****/
public function query($statement){
$keyword = substr(strtoupper($statement), 0, strpos($statement, " "));
$dbh = $this->db_connect();
if($dbh){
try{
$sql = $dbh->prepare($statement);
$exe = $sql->execute();
}
catch(PDOException $err){
return $err->getMessage();
}
switch($keyword){
case "SELECT":
$result = array();
while($row = $sql->fetch(PDO::FETCH_ASSOC)){
$result[] = $row;
}
return $result;
break;
default:
return $exe;
break;
}
}
else{
return false;
}
}
Other PHP:
$db = new Db_class();
$sql = "SQL STATEMENT";
$result = $db->query($sql);
Your constructor is marked as private which means new DB will raise an error. I see you have a private property to store an instance, are you missing the singleton method to return a new object?
I am trying to change the following code to use MySqli instead of MySql. I have removed some methods that seem unimportant to what I'm addressing here.
class db {
var $hostname,
$database,
$username,
$password,
$connection,
$last_query,
$last_i,
$last_resource,
$last_error;
function db($hostname=DB_HOSTNAME,$database=DB_DATABASE,$username=DB_USERNAME,$password=DB_PASSWORD) {
$this->hostname = $hostname;
$this->database = $database;
$this->username = $username;
$this->password = $password;
$this->connection = mysql_connect($this->hostname,$this->username,$this->password) or $this->choke("Can't connect to database");
if($this->database) $this->database($this->database);
}
function database($database) {
$this->database = $database;
mysql_select_db($this->database,$this->connection);
}
function query($query,$flag = DB_DEFAULT_FLAG) {
$this->last_query = $query;
$resource = mysql_query($query,$this->connection) or $this->choke();
list($command,$other) = preg_split("|\s+|", $query, 2);
// Load return according to query type...
switch(strtolower($command)) {
case("select"):
case("describe"):
case("desc"):
case("show"):
$return = array();
while($data = $this->resource_get($resource,$flag)) $return[] = $data;
//print_r($return);
break;
case("replace"):
case("insert"):
if($return = mysql_insert_id($this->connection))
$this->last_i = $return;
break;
default:
$return = mysql_affected_rows($this->connection);
}
return $return;
}
function resource_get($resource = NULL,$flag = DB_DEFAULT_FLAG) {
if(!$resource) $resource = $this->last_resource;
return mysql_fetch_array($resource,$flag);
}
}
This is what I've got so far:
class db {
var $hostname = DB_HOSTNAME,
$database = DB_DATABASE,
$username = DB_USERNAME,
$password = DB_PASSWORD,
$connection,
$last_query,
$last_i,
$last_resource,
$last_error;
function db($hostname, $database, $username, $password) {
$this->hostname = $hostname;
$this->database = $database;
$this->username = $username;
$this->password = $password;
$this->connection = new mysqli($this->hostname, $this->username, $this->password, $this->database) or $this->choke("Can't connect to database");
if (mysqli_connect_errno())
{
echo "Failed to connect to MySQL: " . mysqli_connect_error();
}
if($this->database)
$this->database($this->database);
}
function database($database) {
$this->database = $database;
mysqli_select_db($this->connection, $this->database );
}
function query($query, $flag = DB_DEFAULT_FLAG) {
$this->last_query = $query;
//print_r($query);
$result = mysqli_query($this->connection, $query) or $this->choke("problem connecting to DB");
while($row=mysqli_fetch_assoc($result)) {
$resource[]=$row;
}
//print($command);
//print_r($resource);print("<br>");
list($command, $other) = preg_split("|\s+|", $query, 2);
// Load return according to query type...
switch(strtolower($command)) {
case("select"):
case("describe"):
case("desc"):
case("show"):
$return = array();
while($data = $this->resource_get($resource, $flag))
$return[] = $data;
//print_r($return);
break;
case("replace"):
case("insert"):
if($return = mysqli_insert_id($this->connection))
$this->last_i = $return;
break;
default:
$return = mysqli_affected_rows($this->connection);
}
return $return;
}
function resource_get($resource = NULL, $flag = DB_DEFAULT_FLAG) {
if(!$resource)
$resource = $this->last_resource;
return mysqli_fetch_array($resource, $flag);
}
So here's the problem: I've checked the results with a print_r() and the $resource array is loading correctly, but the value of $return when checked with print_r() just ends up being "Array()". Therefore, as near as I can figure, something isn't being handled correctly in this part of the code, which is why I included the resource_get() function call:
$return = array();
while($data = $this->resource_get($resource, $flag))
$return[] = $data;
//print_r($return);
break;
If I use mysqli_fetch_row($resource, $flag) instead of mysqli_fetch_array($resource, $flag) I still get the same result, i.e. print_r($return) yields simply "Array()".
The variable $resource does not represent a mysqli_result resource object at the time you pass it into $this->resource_get(). Instead, it is already a 2D array of results since you previously ran a mysqli_fetch_assoc() loop.
To make this work with your current code, you may either remove the earlier fetch loop:
$result = mysqli_query($this->connection, $query) or $this->choke("problem connecting to DB");
// Remove this
//while($row=mysqli_fetch_assoc($result)) {
// $resource[]=$row;
//}
And later, pass $result instead of $resource into your resource_get() method since it is $result that is the resource object.
Or, you might just skip the resource_get() call entirely and return $resource directly since it already contains the result array.
I am very new to programming with PHP and am working on a fun little game to help myself learn. I got some code help from others on pulling a character's stats from the DB but am having trouble getting it to work. I just get "server error" when I try to run it right now. The Database information is fine, and I previously had a working function that pulled from the DB, but wanted to universalize it through a class function. Here is what I have so far.
DB class:
<?php
class db_class
{
//db connection portion
protected $mysqli;
private $db_host = 'XXXXXXX';
private $db_user = 'Filler';
private $db_password = 'Filler';
protected $db_name = 'Filler';
//db connection portion
public function __construct($db_host = null, $db_user = null, $db_password = null, $db_name = null) {
if (!empty($db_host)) {
$this->db_host = $db_host;
}
// validate other parameters similarly
//database connection object
$mysqli = new mysqli($this->db_host, $this->db_user, $this->db_password, $this->db_name);
if ($mysqli->connect_error) {
throw new Exception('Connect Error: ' . $mysqli->connect_errno . ', ' . $mysqli->connect_error);
} else {
$this->mysqli = $mysqli;
}
}
public function getPlayerStats($id) {
if (empty($id)) {
throw new Exception ('An empty value was passed for id');
}
// verify this is integer-like value
$id = (string) $id;
$pattern = '/^\d+$/';
if (!preg_match($pattern, $id) !== 1) {
throw new Exception ('A non-integer value was passed for id');
}
$id = (int) $id;
$query = "SELECT id, name, strength, defense, level, health, type, experience FROM characters WHERE id = :id";
$stmt = $this->mysqli->prepare($query);
$stmt->bind_param('i', $id);
$result = $stmt->execute();
if (false === $result) {
throw new Exception('Query error: ' . $stmt->error);
} else {
$obj = new stdClass();
$stmt->bind_result($obj->id, $obj->name, $obj->strength, $obj->defense, $obj->level, $obj, health, $obj->type, $obj->experience);
$stmt->fetch();
$stmt->close();
return $obj;
}
}
}
?>
DB class function call:
<?php
include "db_class.php";
echo "made it out here1";
$classobject = new db_class();
echo "made it out here2";
$results = $classobject->getPlayerStats('1');
print_r($results);
echo "made it out here3";
$id = "id: " . $results['id'];
$name = "name: " . $results['charname'];
$strength = "strength: " . $results['strength'];
$defense = "defense: " . $results['defense'];
$health = "health: " . $results['health'];
$level = "level: " . $results['level'];
$type = "type: " . $results['type'];
$experience = "experience: " . $results['experience'];
echo "<br/>";
echo "made it out here4";
?>
It is difficult to debug this code since I'm used to just putting in breaklines and running through coding errors in things like VBA in compilers, so any debugging tips would be greatly helpful. What am I doing wrong here? Thanks in advance!
You wrote
public __construct($db_host = NULL, ...
but constructors are functions. You need
public function __construct($db_host = NULL, ...
Your db_class constructor accepts four parameters. This instantiation passes none.
$classobject = new db_class();
So you end up with junk in your connection string. Sort that out and you'll be on your way.
You can avoid a lot of debugging by building minimal versions that work. For example, you can write this first.
<?php
class db_class{
public function __construct($db_host = NULL, $db_user = NULL, $db_password = NULL, $db_name = NULL) {
}
}
?>
If that works, check it in to version control, then add a little code to it. (How do you know whether it works? Test it.)
I'm a beginner in OOP PHP.
I'm trying to make a class that will connect,query and fetch data
I done the below coding
class MySQL {
private $set_host;
private $set_username;
private $set_password;
private $set_database;
public function __Construct($set_host, $set_username, $set_password){
$this->host = $set_host;
$this->username = $set_username;
$this->password = $set_password;
$con= mysql_connect($this->host, $this->username, $this->password);
if(!$con){ die("Couldn't connect"); }
}
public function Database($set_database)
{
$this->database=$set_database;
mysql_select_db($this->database)or die("cannot select Dataabase");
}
public function Fetch($set_table_name){
$this->table_name=$set_table_name;
$query=mysql_query("SELECT * FROM ".$this->table_name);
$result= mysql_fetch_array($query);
}
}
$connect = new MySQL('localhost','root','');
$connect->Database('cms');
$connect->Fetch('posts');
what I'm trying to achieve is this
$connect = new MySQL('localhost','root','');
$connect->Database('cms');
$connect->Fetch('posts');
and I want to fetch the data using a format like this
echo $result[0];
but I'm not getting that logic to make this happen
please help
Thanks!
Your Fetch function is only pulling one row from the database, and you aren't returning the results...
The method isn't the best, but in order to achieve what you're trying to do:
public function Fetch($set_table_name){
$query=mysql_query("SELECT * FROM ".$set_table_name);
$result = array();
while ($record = mysql_fetch_array($query)) {
$result[] = $record;
}
return $result;
}
This will make each row a part of $result, but you'll have to access it like this:
You would call the fetch function like this:
$result = $connect->Fetch('posts');
echo $result[0]['columnName']; // for row 0;
Or in a loop:
for ($x = 0; $x < count($result); $x++) {
echo $result[$x][0] . "<BR>"; // outputs the first column from every row
}
That said, fetching the entire result set into memory is not a great idea (some would say it's a very bad idea.)
Edit: It also looks like you have other issues with your class... I have to run but will check back tomorrow and if others haven't set you straight I will expand.
Edit2: Ok, going to do a once-over on your class and try to explain a few things:
class MySQL {
//declaring the private variables that you will access through $this->variable;
private $host;
private $username;
private $password;
private $database;
private $conn; // Adding the connection, more on this later.
public function __Construct($set_host, $set_username, $set_password){
$this->host = $set_host;
$this->username = $set_username;
$this->password = $set_password;
// Combining the connection & connection check using 'or'
// Notice that I removed the semi-colon after the mysql_connect function
$this->conn = mysql_connect($this->host, $this->username, $this->password)
or die("Couldn't connect");
}
public function Database($set_database)
{
$this->database=$set_database;
// Adding the connection to the function allows you to have multiple
// different connections at the same time. Without it, it would use
// the most recent connection.
mysql_select_db($this->database, $this->conn) or die("cannot select Dataabase");
}
public function Fetch($table_name){
// Adding the connection to the function and return the result object instead
return mysql_query("SELECT * FROM ".$table_name, $this->conn);
}
}
$connect = new MySQL('localhost','root','');
$connect->Database('cms');
$posts = $connect->Fetch('posts');
if ($posts && mysql_num_rows($posts) > 0) {
echo "Here is some post data:<BR>";
while ($record = mysql_fetch_array($posts)) {
echo $record[0]; // or a quoted string column name instead of numerical index.
}
} else {
echo "No posts!";
}
I hope this helps... It should get you started at least. If you have more questions you should ask them separately.
That's because $result is set inside the Fetch function. It won't be available outside the Fetch function.
Instead of this line $result= mysql_fetch_array($query);, you'll want something like return mysql_fetch_array($query);.
And then in your code
$row = $connect->Fetch('posts');
// do something with $row
On another note, your Fetch function only applies to database queries that return one row. You'll have to separate the mysql_query & mysql_fetch_array calls into another function if you want to loop through rows in a query result.
And on another note, you shouldn't need to encapsulate this code into a class. PHP already provides OOP-based database classes called PDO, or PHP Data Objects. There's a learning curve to it, but it's best practice, and will help secure your code against things like SQL injection.
This is a pretty good tutorial: http://www.giantflyingsaucer.com/blog/?p=2478
I would make a function that returns the value of the object.
public function returnData($data){
return $this->$data;
}
Then within the page you wish to get the data on just initiate the class and call the function within that class.
$post->returnDate("row name here");
<?php
//database.php
class Databases{
public $con;
public function __construct()
{
$this->con = mysqli_connect("localhost", "root", "", "giit");
if(!$this->con)
{
echo 'Database Connection Error ' . mysqli_connect_error($this->con);
}
}
public function insert($table_name, $data)
{
$string = "INSERT INTO ".$table_name." (";
$string .= implode(",", array_keys($data)) . ') VALUES (';
$string .= "'" . implode("','", array_values($data)) . "')";
if(mysqli_query($this->con, $string))
{
return true;
}
else
{
echo mysqli_error($this->con);
}
}
public function selectmulti($selecttype,$table_name)
{
$array = array();
$query = "SELECT ".$selecttype." FROM ".$table_name."";
$result = mysqli_query($this->con, $query);
while($row = mysqli_fetch_assoc($result))
{
$array[] = $row;
}
return $array;
}
public function selectsingle($selecttype,$table_name)
{
$query = "SELECT ".$selecttype." FROM ".$table_name."";
$result = mysqli_query($this->con, $query);
$row = mysqli_fetch_assoc($result);
return $row;
}
}
?>
<?php
$data = new Databases;
$post_data = $data->selectmulti('*','centerdetail');
$n = 1;
foreach($post_data as $post)
{
echo $n.'.'.$post['CenterCode'].'___';
$n += 1;
}
echo '<br>';
$post_data = $data->selectsingle('*','centerdetail');
echo $post_data['CenterCode'];
?>