codeigniter variable as variable using Different Method

Question

$i = 2;

$this->variable2 = "test"; // $this->variable2 is defined

$this->variable= '$this->variable'.$i;

echo ${$this->variable};

Error

A PHP Error was encountered

Severity: Notice

Message: Undefined variable: $this->variable2

Answer 1

This Method Using Different Type of uses.

Finaly i found the solution

Create Variable in one Function method

Update Variable in Another Function method

Call Variable in Different Function methods

But never call Variable name Directly!!!.

public function BWT_start($i){
    global $varx;
    
    $varx = 'var'.$i;
    
    return $varx;
}

// Call Global Variable With Different Method with Never call Variable name Directly!!!.
public function BWT_run(){
    
    global $varx;
    
    for($i=1;$i<=7;$i++){
        $this->BWT_start($i); //echo Show created Variable Name

        $this->BWT_update($i); //echo Show updated Variable value
        
        $this->BWT_process($i); //echo Show Again Changed Variable value
    }
}

public function BWT_update($i){
    global $varx; global $$varx;
    
    $$varx = "DB_ROW_$i<br>";

    return $$varx;
    // 
}

public function BWT_process($i){
    $vary = 'var'.$i;
    global $$vary;
    $$vary = "DB_UPDATE_$i<br>";
    return $$vary;
}