解析错误：语法错误，C：\xampp\htdocs\sms\include\result.php 中的意外"$this"(T_VARIABLE)

Question

<?php
    class Result{
        protected $db_table        =  "result";
        protected $db_table_fields =  array();
        public $english;
        public $urdu;
        public $math;
        public $physics;
        public $chemistry;
        public $biology;
        public $english_grade;
        public $urdu_grade;
        public $math_grade;
        public $physics_grade;
        public $chemistry_grade;
        public $biology_grade;
        public function grading(){
            if($this->english >= 90 && $this->english <= 100)
                $this->english_grade = "A";
            else if($this->english >= 80 && $this->english < 90)
                $this->english_grade = "B";
            else if($this->english >= 70 && $this->english < 80)
                $this->english_grade = "C";
            else if($this->english >= 50 && $this->english < 70)
                $his->english_grade  = "D";
            else ($this->english >= 0 && $this->english <  50)
                $this->english_grade = "Fail";
        }
    }//class ends here
?>

Answer 1

else ($this->english >= 0 && $this->english <  50)
     $this->english_grade = "Fail";

其他不期望的条件，这就是$this出乎意料的原因。

$his->english_grade  = "D";

这看起来也是另一个会影响功能的错误。