protected function getForeignKeyName()
    {
        if (method_exists($this->relation, 'getQualifiedForeignPivotKeyName')) {
            $method = 'getQualifiedForeignPivotKeyName'; // Laravel 5.5
        } elseif (method_exists($this->relation, 'getQualifiedForeignKeyName')) {
            $method = 'getQualifiedForeignKeyName'; // Laravel 5.4
        } else {
            $method = 'getForeignKey'; // Laravel 5.3
        };

        return last(explode('.', $this->relation->$method()));
    }
protected function getForeignKeyName()
    {
        if (method_exists($this->relation, 'getQualifiedForeignPivotKeyName')) {
            $method = 'getQualifiedForeignPivotKeyName'; // Laravel 5.5
        } elseif (method_exists($this->relation, 'getQualifiedForeignKeyName')) {
            $method = 'getQualifiedForeignKeyName'; // Laravel 5.4
        } else {
            $method = 'getForeignKey'; // Laravel 5.3
        };

        return last(explode('.', $this->relation->$method()));
    }
protected function getForeignKeyName ( ) { if ( method_exists ( $ this -> relation , 'getQualifiedForeignPivotKeyName' ) ) { $ method = 'getQualifiedForeignPivotKeyName' ; // Laravel 5.5 } elseif ( method_exists ( $ this -> relation , 'getQualifiedForeignKeyName' ) ) { $ method = 'getQualifiedForeignKeyName' ; // Laravel 5.4 } else { $ method = 'getForeignKey' ; // Laravel 5.3 } ; return last ( explode ( '.' , $ this -> relation -> $ method ( ) ) ) ; }
Get the foreign key for the relation.

@return string
Get the foreign key for the relation .