js给dropdownlist添加选项的小例子

  

复制代码 代码如下:

  <input name="" type="text"  id="newDirtxt"/>

  <input class="btn" name="" type="button" value="创建新目录"  onclick="newDir()" />

  

  ?<BR><BR><BR>Js代码 <BR><BR><script type="text/javascript">

  ////创建新目录

  function newDir() {

  var txt = document.getElementById("newDirtxt");

  var dirname = txt.value;

  if (dirname) {

  alert("请填写目录名");

  } else {

  $.ajax({

  type: "Post",

  url: "/center/directorynew",

  async: false,

  data: { dirname: dirname },

  success: function(msg) {

  if (msg.length < 40) {

  var DirectoryID = document.getElementById("DirectoryID");

  var tOption = document.createElement("Option");

  tOption.text = dirname;

  tOption.value = msg;

  DirectoryID.appendChild(tOption);

  txt.value = "";

  alert("增加成功");

  } else {

  alert("增加失败");

  }

  }

  });

  }//else

  }

  </script><BR><BR><BR>后台代码 <BR><BR>返回刚刚插入的目录的id字符串 <BR>