按返回键返回页面后，索引未重置为0

Question

Following is the script that makes a jump menu.Using javascript i have set the index of the options tag to be equal to 0.The scrip works fine except one.After i jump to another page from the jump menu the index is not reset to the index 0.Instead it is set to the index where i had clicked.Why is it so ? 以下是制作跳转菜单的脚本。使用javascript，我将options标签的索引设置为等于0.除了一个以外，该脚本均正常运行。从跳转菜单跳转到另一页后，索引未重置为索引0.相反，它设置为我单击过的索引。为什么这样？ What is the problem with script ? 脚本有什么问题？

script: 脚本：

window.onload = startInit;

function startInit() {
document.getElementById("newLocation").selectedIndex = 0;
document.getElementById("newLocation").onchange = jumpPage;
}

function jumpPage() {
var newLoc = document.getElementById("newLocation");
var newPage = newLoc.options[newLoc.selectedIndex].value;
if(newPage != "")
   window.location = newPage;
}

HTML 的HTML

<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Untitled Document</title>
<script type="text/javascript" src="script.js">
</script>
</head>

<body bgcolor="#FFFFCC">
<center>
<form>
<select id="newLocation">
 <option value="myworld.gif">first</option>
 <option value="myhome.gif">second</option>
 <option value="myroom.gif">third</option>
 <option value="mybed.jpg">fourth</option>
</select>
</form>

Answer 1

Browser acts smart and caches your page. 浏览器行为聪明，并缓存您的页面。 So are seeing the cached version of your HTML page.To ensure that this doesn't happen and you always start up with the 0th index,tell the browser not to do anything (the way you want) when the page unloads. 因此，请参见HTML页面的缓存版本。为确保不会发生这种情况，并始终使用0th索引启动，请告诉浏览器在页面卸载时不执行任何操作（您想要的方式） 。

The statement should be: window.onunload = function(){}; // do nothing function 该语句应为： window.onunload = function(){}; // do nothing function window.onunload = function(){}; // do nothing function

you can add after window.onload = startInit; 您可以在window.onload = startInit;之后添加window.onload = startInit;

That tells the browser that something happened during unloading and therefore it should re-read the page. 这告诉浏览器卸载过程中发生了某些事情，因此应该重新读取页面。

按返回键返回页面后，索引未重置为0

问题描述

1 个解决方案

解决方案1
1 已采纳 2011-09-19 14:40:48

按返回键返回页面后，索引未重置为0

问题描述

1 个解决方案

解决方案1 1 已采纳 2011-09-19 14:40:48

解决方案1
1 已采纳 2011-09-19 14:40:48