The following example will demonstrate a poll where the result is shown without reloading.

When a user choose an option above, a function called "getVote()" is executed. The function is triggered by the "onclick" event

<html>
<head>
<script type="text/javascript">
function getVote(int)
{
if (window.XMLHttpRequest)
  {// code for IE7+, Firefox, Chrome, Opera, Safari
  xmlhttp=new XMLHttpRequest();
  }
else
  {// code for IE6, IE5
  xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
  }
xmlhttp.onreadystatechange=function()
  {
  if (xmlhttp.readyState==4 && xmlhttp.status==200)
    {
   document.getElementById("poll").innerHTML=xmlhttp.responseText;
    }
  }
xmlhttp.open("GET","poll_vote.php?vote="+int,true);
xmlhttp.send();
}
</script>
</head>
<body>

 

<div id="poll">
<h3>Do you like PHP and AJAX so far?</h3>
<form>
Yes:
<input type="radio" name="vote"value="0" onclick="getVote(this.value)" />
<br />No:
<input type="radio" name="vote"value="1" onclick="getVote(this.value)" />
</form>
</div>

</body>
</html>

 

The getVote() function does the following:

  • Create an XMLHttpRequest object
  • Create the function to be executed when the server response is ready
  • Send the request off to a file on the server
  • Notice that a parameter (vote) is added to the URL (with the value of the yes or no option)

判断控件的disabled属性是不是true,是的话return false;实现禁用radio的onclick事件并可再次启用它

方法一:(同时实现禁用,重新启用功能,只能针对button text类型的INPUT,对div无法禁用其onclick事件)

<input type="button" value="A button. Click me to see the alert box." onclick="alert('I am clicked.');" id="cmd1" />
<br/>
<input type="button" value="Click me to disable the first button" onclick="document.getElementById('cmd1').disabled=true;" />
<br/>

方法二,三:(实现移除radio的onclick事件,需再次重新注册事件,可以禁用div的onclick事件)
<input type="button" value="Click me to disable the onclick event on first button" onclick="document.getElementById('cmd1').onclick=function(){};" />

 

<br/>

三:
<input type="button" value="Click me to disable the onclick event on first button" onclick="document.getElementById('cmd1').onclick=null;" />

 

部分摘自 http://www.w3schools.com/  

posted on 2010-11-09 12:47  露水丛生  阅读(2653)  评论(0编辑  收藏  举报