如何将这个内联javascript转换为函数？

Question

尝试将内联javascript部分转换为函数的其余部分。

html

<li><a href="javascript:popupManager.open('http://www.google.com', 'google')">google</a></li>

JS

 function PopupManager() {
 this.name = "_popupmanager_";
 this.windows = {};
 };

 PopupManager.prototype.open = function(url, name) {
 this.windows[name] = window.open(url, name);
 this.windows[name].focus();
 };

 PopupManager.prototype.closeAll = function() {
 for (name in this.windows) {
    this.closeWindow(name);
 }
 };

 PopupManager.prototype.closeWindow = function(name) {
 if (this.windows[name]) {
    this.windows[name].close();
    delete this.windows[name];
 }
 };

我试过

HTML

 <li><a href="javascript:void(0)" id="popupManager">google</a>

JS

 document.getElementById("popupManager").onclick = function () { 
 var popupManager = new PopupManager();
 function PopupManager() {
 this.name = "_popupmanager_";
 this.windows = {};

 };
 };
 document.getElementById("popupManager").onclick = function () { 
 var popupManager = new PopupManager();
 PopupManager.prototype.open = function(url, option, size, name) {
 var url = "http://google.com" 
 var option = "null, status=no, toolbar=no, menubar=no, titlebar=no, 
 location=no, scrollbars=no, resizable=no"
 var size = 'height=200, width = 814'
 this.windows[name] = window.open(url, option, size, name);
 this.windows[name].focus();
 };


 PopupManager.prototype.closeAll = function() {
 for (name in this.windows) {
    this.closeWindow(name);
 }
 };

我需要将js与html分开的原因是我正在为href链接设置一长串选项。实际上，我甚至不想要一个href链接。

我正在尝试使用这样的按钮。

<button id="popupManager">google</button> 

控制台错误显示“PopupManager未定义”。好吧，我已加入

 var popManager = document.getElementById("popupManager");

但我得到同样的错误＆amp;我很难过。

我对这里的错误一无所知。