如何阻止多个书签出现？

Question

I am in the process of making a bookmarklet that pops up a div with various things in it... when you click on the link to open the bookmarklet twice, two bookmarklets pop up.我正在制作一个小书签，它会弹出一个包含各种内容的 div……当您单击链接两次打开小书签时，会弹出两个小书签。 how do I prevent this from happening?我该如何防止这种情况发生？

index.html:索引.html：

<html>
<head>
<title>Bookmarklet Home Page</title>
<link rel="shortcut icon" href="favicon.ico" />
</head>
<body>
<a href="javascript:(function(){code=document.createElement('SCRIPT');code.type='text/javascript';code.src='code.js';document.getElementsByTagName('head')[0].appendChild(code)})();">click here</a>
</body>
</html>

code.js:代码.js：

function toggle_bookmarklet() {
    bookmarklet = document.getElementById("bookmarklet");
    if (bookmarklet.style.display == "none") {
        bookmarklet.style.display = "";
    }
    else {
        bookmarklet.style.display = "none";
    }
}
div = document.createElement("div");
div.id = "bookmarklet";
div.style.margin = "auto";
div.style.position = "fixed";
content = "";
content += "<a href='javascript:void(0);'><div id='xbutton' onClick='javascript:toggle_bookmarklet();'>x</div></a>";
div.innerHTML = content;
document.body.appendChild(div);

Answer 1

Just check for the existence of div before creating it.只需在创建之前检查div是否存在。

var div = document.getElementById("bookmarklet");
if (!div)
{
    div = document.createElement("div");
    div.id = "bookmarklet";
    div.style.margin = "auto";
    div.style.position = "fixed";
}

Also, since you already have a global reference to div , you don't need to search for it by id in toggle_bookmarklet .此外，由于您已经拥有对div的全局引用，因此您无需在toggle_bookmarklet中通过 id 搜索它。 You can just reference div .你可以参考div 。 I'd try to choose a more unique name though, so as to avoid running in to naming collisions.不过，我会尝试选择一个更独特的名称，以避免遇到命名冲突。

Edit: For that matter, if you are going to use a global variable, you can simplify further.编辑：就此而言，如果您要使用全局变量，则可以进一步简化。 Don't even bother giving it an id, just use the global reference:甚至不用给它一个 id，只需使用全局引用：

function toggle_bookmarklet() {
    bookmarkletEl.style.display = bookmarkletEl.style.display == "none" ? "" : "none";
}
if (!window.bookmarkletEl) {
    var bookmarkletEl = ddocument.createElement("div");
    bookmarkletEl.style.margin = "auto";
    bookmarkletEl.style.position = "fixed";
}

如何阻止多个书签出现？

问题描述

1 个解决方案

解决方案1
2 已采纳 2011-06-14 17:34:40

如何阻止多个书签出现？

问题描述

1 个解决方案

解决方案1 2 已采纳 2011-06-14 17:34:40

解决方案1
2 已采纳 2011-06-14 17:34:40