javascript - 从另一个文件包含的文件运行 javascript 函数

Question

我们使用 document.write 从另一个 javascript 文件中包含一个 javascript 文件。在第一个 javascript 文件中调用了第二个 javascript 文件中的函数。结果，我们收到一条错误消息:调试代码时未定义“gMunchkin”。我做错了什么，“gMunchkin”怎么能这样称呼？

我用IE7看Demo:http://www.apus.edu/bin/r/u/test.htm

Answer 1

很可能在您调用 mktoMunchkin() 时浏览器尚未完成下载 munchkin.js。

你可以使用 jQuery to load muchkin.js.

$.getScript('http://munchkin.marketo.net/munchkin.js', function() {
     //The code inside this anonymous function is executed by $.getScript() when the script has finished 
     //downloading.It is called a Callback function. It is required because 
     //getScript() does not block and will return before the javascript file is 
     //downloaded by the client
     //If the call to getScript was blocking, the client would be frozen until the 
     //js file was downloaded, which could be seconds and could lead the user 
     //to think the browser has crashed
     alert('Muchkin loaded. We can now use the Munchkin library.');
     mktoMunchkin("476-IFP-265");
});
//any code placed here will execute immediately. When this code is executed,
// munchkin.js may not have finished downloading. Hopefully you can see why 
//there is a need for the callback function in $.getScript().

这样你就可以保证 munchkin.js 在尝试使用它的功能之前已经完全下载。