附加 jQuery 事件处理程序,以便它们首先被触发 [英] Attaching jQuery event handlers so that they are triggered first
问题描述
有没有办法附加一个 jQuery 事件处理程序,以便在任何先前附加的事件处理程序之前触发该处理程序?我遇到了这篇文章,但代码没有工作是因为事件处理程序不再存储在数组中,这是他的代码所期望的.我试图创建一个 jQuery 扩展来做我想做的事,但这不起作用(事件仍然按照它们绑定的顺序触发):
Is there a way to attach a jQuery event handler such that the handler is triggered before any previously-attached event handlers? I came across this article, but the code didn't work because event handlers are no-longer stored in an array, which is what his code expected. I attempted to create a jQuery extension to do what I wanted, but this is not working (the events still fire in the order they were bound):
$.fn.extend({
bindFirst: function(type, handler) {
var baseType = type;
var dotIdx = type.indexOf('.');
if (dotIdx >= 0) {
baseType = type.substr(0, dotIdx);
}
this.each(function() {
var oldEvts = {};
var data = $.data(this);
var events = data.events || data.__events__;
var handlers = events[baseType];
for (var h in handlers) {
if (handlers.hasOwnProperty(h)) {
oldEvts[h] = handlers[h];
delete handlers[h];
// Also tried an unbind here, to no avail
}
}
var self = $(this);
self.bind(type, handler);
for (var h in oldEvts) {
if (oldEvts.hasOwnProperty(h)) {
self.bind(baseType, oldEvts[h]);
}
}
});
}
});
是否有一种自然的方式来重新排序事件处理?如果没有,你知道我可以应用的技术吗?我使用的是 jQuery 1.4.1,但如果需要我会升级.
Is there a natural way to reorder event handling? If there isn't, do you know of technique I could apply? I'm using jQuery 1.4.1, though I'll upgrade if I must.
推荐答案
这是我不久前制作的一个简单插件.允许您将处理程序绑定到列表的开头.它非常简单,我不保证它适用于命名空间事件或任何非常奇特的事情.
Here's a simple plugin I did a while back. Lets you bind a handler to the beginning of the list. It is very simple, and I wouldn't guarantee that it works with namespaced events or anything terribly fancy.
对于简单地绑定单个或空间独立的事件组,它应该可以工作.
For simply binding a single or space separate group of events, it should work.
示例: http://jsfiddle.net/gbcUy/
$.fn.bindUp = function(type, fn) {
type = type.split(/s+/);
this.each(function() {
var len = type.length;
while( len-- ) {
$(this).bind(type[len], fn);
var evt = $.data(this, 'events')[type[len]];
evt.splice(0, 0, evt.pop());
}
});
};
或者,如果您想以其他方式操作处理程序数组,只需获取您想要的元素的处理程序,然后按照您的意愿操作它:
Or if you wanted to manipulate the Array of handlers in some other manner, just get the handlers for the element you want, and manipulate it however you want:
示例: http://jsfiddle.net/gbcUy/1/
var clickHandlers = $('img').data('events').click;
clickHandlers.reverse(); // reverse the order of the Array
这篇关于附加 jQuery 事件处理程序,以便它们首先被触发的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!