数组

<!--数组中包含 对象元素 函数 数组-->
  <!--数组的创建-->
  <!--<script type="text/javascript">
//   1.常规方法
//    var array = new Array();
//    array[0] = "1";
//    array[1] = "2";
//    array[2] ="3";
//   2. 简洁方法
//    var array = new Array("1", "2","3");
//   3.字面
//   var array = ["1","2","3"] ;
  </script>-->
  <!--<script type="text/javascript">
//   var array = ["1","2","3"];
//   访问一个数组  下标是0数组第一个元素  而1为数组第二个元素
//   document.write(array[2]);
//   修改一个数组第一位
//   array[0]="100";
//   document.write(array);
//   合并两个数组
//   var fruit = ["apple" ,"cherry"] ;
//   var vegetable = ["tomato"];
//   var all = fruit.concat(vegetable);
//   document.write(all+" ");
//   合并三个数组
//   var fruit = ["apple" ,"cherry"] ;
//   var meat = ["beef"];
//   var vegetable = ["tomato"];
//   var all = fruit.concat(vegetable ,meat);
//   document.write(all+" ");
  </script>-->
  <!--<p id="demo"></p>
  <button onclick="group()"  >点击</button>
  <script type="text/javascript">
   var array =["you ","me","and","I"];
   function group(){
    array.reverse();
    var place=document.getElementById("demo");
    var place =document.getElementById("demo");
    place.innerHTML = array;
   }
    
  </script>-->