我如何把这个jQuery变成javascript？

Question

I have a facebook connect button on this site here is the code

 <fb:login-button onlogin="javascript:jfbc.login.login_button_click();"
 perms="email,publish_stream,user_about_me,user_hometown,user_location,user_birthday,user_religion_politics,user_interests,user_activities,user_website" 
size="medium" v="2"><a class="fb_button fb_button_medium">
<span class="fb_button_text"\>Login With Facebook</span></a></fb:login-button>

and i want to trigger this button with a javascript call and doing research i found this jquery that seems that it would do the trick (havent tested though) and i was wondering if there is an equivelent javascript or mootool because jquery is not installed. I can install it if i cant find a solution. Or if anyone has another idea on how to trigger this facebook button

$("fb\:login-button").trigger("click");

Answer 1

您应该能够只调用内联调用的相同代码：

jfbc.login.login_button_click();

Answer 2

There are two ways to "trigger" a listener:

1. call it directly (eg element.onclick() )
2. dispatch an event into the DOM that the listener will respond to

The trouble with the first method is that it doesn't replicate a bubbling event so the listener may not work as intended (eg there is no associated event object or bubbling, the listener's this keyword may not be correctly set).

The trouble with the second is that some browsers will not allow programatically dispatched events to do certain things (click on links for example). Also, in some browsers you have to use the W3C dispatchEvent and in others the Microsoft fireEvent .

So unless the listener has been designed specifically to work with one method or the other and is called appropriately, your chances of triggering the listener successfully are quite low.

PS. Some libraries provide their own event system, with custom events and bubbling of otherwise non-bubbling events, but in that case you have to set and trigger the listener using that library, otherwise it will probably not respond to either of the above methods.

Answer 3

I ran into this tonight, absolutely positioned a new button image over the iframe, and was planning on using pointer-events:none to pass through and click the iframe, but I was looking for a cross-browser solution, here you go.

jQuery('.button_fb_connect').live('click', function(){  FB.login() })

Your simply running the js function FB.login() after clicking your new element, obviously you can use whatever event you want.

Thats in jQuery of course, but thats the function you want, not just a simple click event trigger.

Answer 4

I suppose it would be something like

document.getElementsByTagName("fb\:login-button")[0].click();

I'm sure that would work very well with a "normal" DOM element that handles the click event; however, I'm not entirely sure it will work in all browsers with the fb:login-button element shimmed into HTML. You'll have to let me know.

Answer 5

看起来你应该能够做到：

document.body.getElementsByTagName("fb\:login-button")[0].click();

Answer 6

It looks like you want a namespaced element selector, so you should use:

document.getElementsByTagNameNS('fb', 'login-button')[0].click();

The : is the namespace separator.