I want to use a method inside another method in PHP OOP

Question

I want to instantiate an object like this:

$foo=new myClass();
$foo->method1()->method2();

How I will set the class for this?

`method1()` has to return something that has a `method2()`. But what is it that you *really* want to achieve? — Biffen, Jan 10 '15 at 11:19
I want to make a database class. I want to write codes like this $db->select("*/custom")->from("table"); — Mahmoodur, Jan 10 '15 at 11:22

score 3 · Accepted Answer · edited May 23 '17 at 12:28

3

You need to return in this method $this As example:

class A
{
     function first()
     {
         //do some stuff
          return $this;
     }
     function second()
     {
         //do some stuff
          return $this;
     }
}

$obj = new A();
$obj->first()->second();

There is a pattern "Fluent intarface", some simple example. And check this.

edited May 23 '17 at 12:28

Community

1
1

answered Jan 10 '15 at 11:21

sergio

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He doesn't `need` to return `$this`, what he `need`s to return is an object with the method he is chaining. It could be any instance with the right implementations of a method being called in the chain (which also implies the possibility that `$this` implements the method being called in the chain). – dbf Jan 10 '15 at 21:23

score 3 · Answer 2 · answered Jan 10 '15 at 11:36

I think your code should look something like this:

(Code is not complete it only should give the idea how it could work)

<?php

    class Database {

        private $hostname = "localhost";
        private $dbName = "dbName";
        private $username = "root";
        private $password = "";

        private $connection;

        private $queryString = "";

        public function __construct($hostname, $dbName, $username, $password) {

            $this->hostname = $hostname;
            $this->dbName = $dbName;
            $this->username = $username;
            $this->password = $password;

            try {
                $this->connection = new PDO("mysql:host=" . $this->hostname . ";dbname=" . $this->dbName . "", $this->username, $this->password);
                $this->connection->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

            } catch(PDOException $e) {
                echo $e->getMessage();
            }

        }

        public function Close() {
            $this->connection = null;
        }

        public function Select($select) {

            $this->queryString .= "SELECT $select";

            return $this;

        }

        public function From($from) {

            $this->queryString .= " FROM $from";

            return $this;

        }

        public function Where($column, $value) {

            $this->queryString .= " WHERE $column = '$value'";

            return $this;

        }

        public function execute() {

            $stmt = $this->connection->prepare($this->queryString);
            $stmt->execute();

        }




    }

    $db = new Database("localhost", "dbName", "root", "");
    $db->Select("id")->From("xy")->Where("name", "peter")->execute();

?>

I want to use a method inside another method in PHP OOP

2 Answers2