doupai5450 2016-08-27 14:37
浏览 79
已采纳

如何在php关闭中使用$ this? [重复]

This question already has an answer here:

I have code like this:

class Foo {
   var $callbacks = array();
   function __construct() {
      $this->callbacks[] = function($arg) {
         return $this->bar($arg);
      };
   }
   function bar($arg) {
      return $arg * $arg;
   }
}

and I would like to use $this inside closures, I've try to add use ($this) but this throw error:

Cannot use $this as lexical variable
</div>
  • 写回答

2条回答 默认 最新

  • douzhuican0041 2016-08-27 14:41
    关注

    You cannot use $this as this is an explicit reserved variable for the class inside reference to the class instance itself. Make a copy to $this and then pass it to the use language construct.

    class Foo {
       var $callbacks = array();
       function __construct() {
          $class = $this;
          $this->callbacks[] = function($arg) use ($class) {
             return $class->bar($arg);
          };
       }
       function bar($arg) {
          return $arg * $arg;
       }
    }
    
    本回答被题主选为最佳回答 , 对您是否有帮助呢?
    评论
查看更多回答(1条)

报告相同问题?

悬赏问题

  • ¥15 求MCSCANX 帮助
  • ¥15 机器学习训练相关模型
  • ¥15 Todesk 远程写代码 anaconda jupyter python3
  • ¥15 我的R语言提示去除连锁不平衡时clump_data报错,图片以下所示,卡了好几天了,苦恼不知道如何解决,有人帮我看看怎么解决吗?
  • ¥15 在获取boss直聘的聊天的时候只能获取到前40条聊天数据
  • ¥20 关于URL获取的参数,无法执行二选一查询
  • ¥15 液位控制,当液位超过高限时常开触点59闭合,直到液位低于低限时,断开
  • ¥15 marlin编译错误,如何解决?
  • ¥15 VUE项目怎么运行,系统打不开
  • ¥50 pointpillars等目标检测算法怎么融合注意力机制