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							- <!DOCTYPE html>
 
- <html lang="en">
 
- <head>
 
-     <meta charset="UTF-8">
 
-     <meta name="viewport" content="width=device-width, initial-scale=1.0">
 
-     <title>Document</title>
 
- </head>
 
- <body>
 
-     <div class="box">
 
-         <div class="box1">项目一</div>
 
-         <div class="box2">项目二</div>
 
-         <div class="box3">项目三</div>
 
-         <div class="box4">项目四</div>
 
-         <div class="box5">项目五</div>
 
-     </div> 
 
-     <button id="btn">添加项目</button>
 
-     <script>
 
-         // var aBox = document.getElementsByClassName("box")[0].getElementsByTagName("div");
 
-         var aBox = document.getElementsByClassName("box")[0].children;
 
-         var oBtn = document.getElementById("btn");
 
-         var oBox = document.getElementsByClassName("box")[0];
 
-         // for(var i=0;i<aBox.length;i++){
 
-         //     aBox[i].addEventListener("click",function(){
 
-         //         console.log(this.innerText);
 
-         //     })
 
-         // }
 
-         // 事件委托 通过给父元素绑定事件 来处理内部子元素事件
 
-         oBox.addEventListener("click",function(e){
 
-             console.log(e.target.innerText);
 
-         })
 
-         oBtn.addEventListener("click",function(){
 
-             var oDiv = document.createElement("div");
 
-             oDiv.innerText = "项目六";
 
-             oBox.appendChild(oDiv);
 
-         })
 
-     </script>
 
- </body>
 
- </html>
 
 
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