如何在javascript或jquery中获取html元素的id？

Question

<div class="class1" co="51">
   <div class="class2">
     <label class="class3">
          <input class="4" dataid="8d2" name="dd"  type="radio" />                       

             <span class="quiz-option-text">ff</span>
      </label>
    </div>
  </div>

i have some thing like this , I want id of the INPUT in javascript or jquery how can i do it?

Answer 1

Using javascript:

var radioInput = document.getElementsByName("dd")[0];
var radioInpId = radioInput.id; //will give you id

Answer 2

First your input should have an id attribute

Like this

<Input id="ggg" type="text">

Then you get it as the following in plain javascript:

var myInput =document.getElementById("ggg");

Or using jQuery:

var myInput= $("#ggg");

Answer 3

If you want to get all dataid in document you have to go through all the elementals in the document. see Demo

Example HTML

<div class="class1" co="51">
   <div class="class2">
     <label class="class3">
          <input class="4" dataid="8d2" name="dd"  type="radio" />                       
          <span class="quiz-option-text">ff</span><br>

          <input  dataid="8d3" name="dd"  type="text" />  <br> 
          <input class="4" dataid="8d4" name="dd"  type="text" /> <br>
          <textarea dataid="8d5">fdfd</textarea>  <br>
      </label>
    </div>
  </div>

Jquery

<script type="text/javascript">
$(document).ready(function(){
var id_arr=new Array();
var i=0;

$('textarea,input').each(function(){
     var id=$(this).attr("dataid");
     alert(id);
    id_arr[i]=$(this).attr("dataid");
    i++;

});
 alert(id_arr);
});
</script>