| 1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859 | <!DOCTYPE html><html lang="en"><head>  <meta charset="UTF-8">  <meta http-equiv="X-UA-Compatible" content="IE=edge">  <meta name="viewport" content="width=device-width, initial-scale=1.0">  <title>Document</title>  <style>    *{      margin: 0;      padding: 0;    }    #div1{      width: 300px;      height: 300px;      background: greenyellow;    }    #div2{      width: 200px;      height: 200px;      background: red;    }    #div3{      width: 100px;      height: 100px;      background: orange;    }  </style></head><body>  <div id="div1">    <div id="div2">      <div id="div3"></div>    </div>  </div>  <script>    /*     js的事件流  从触发事件到处理事件的整个流程    包括事件捕获和事件冒泡    */    var div1 = document.getElementById('div1')    var div2 = document.getElementById('div2')    var div3 = document.getElementById('div3')    div1.addEventListener('click',function(){      console.log(111)    },true)    div2.addEventListener('click',function(){      console.log(222)    },true)    // div3.addEventListener('click',function(){    //   console.log(333)    // },true)    div3.onclick = function(){      console.log(333)    }  </script></body></html>
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