如何为这个扩展jquery ?

   (function () {
        var ev = new $.Event('remove'),
            orig = $.fn.remove;
        var evap = new $.Event('append'),
           origap = $.fn.append;
        $.fn.remove = function () {
            $(this).trigger(ev);
            return orig.apply(this, arguments);
        }
        $.fn.append = function () {
            $(this).trigger(evap);
            return origap.apply(this, arguments);
        }
    })();
    $(document).on('append', function (e) { /*write your logic here*/ });
    $(document).on('remove', function (e) { /*write your logic here*/ });

Jquery 1.9+已经建立了对此的支持(我听说没有测试过)。

使用MutationObserver界面，如Gabriele Romanato的博客所示

找到了，Chrome 18+，火狐14+

// The node to be monitored
var target = $( "#content" )[0];

// Create an observer instance
var observer = new MutationObserver(function( mutations ) {
  mutations.forEach(function( mutation ) {
    var newNodes = mutation.addedNodes; // DOM NodeList
    if( newNodes !== null ) { // If there are new nodes added
        var $nodes = $( newNodes ); // jQuery set
        $nodes.each(function() {
            var $node = $( this );
            if( $node.hasClass( "message" ) ) {
                // do something
            }
        });
    }
  });    
});

// Configuration of the observer:
var config = { 
    attributes: true, 
    childList: true, 
    characterData: true 
};

// Pass in the target node, as well as the observer options
observer.observe(target, config);

// Later, you can stop observing
observer.disconnect();

2015年更新，新的MutationObserver被现代浏览器支持:

找到了，Chrome 18+，火狐14+

如果您需要支持较老的方法，您可以尝试使用其他方法，例如下面这个5年(!)年前的答案中提到的方法。那里有龙。享受:)

其他人正在更改文档?因为如果你可以完全控制这些变化，你只需要创建你自己的domChanged API——用一个函数或自定义事件——并在你修改东西的地方触发/调用它。

DOM Level-2有突变事件类型，但是旧版本的IE不支持它。请注意，突变事件在DOM3事件规范中已弃用，并且具有性能损失。

你可以尝试在IE中使用onpropertychange来模拟突变事件(如果它们都不可用，则退回到蛮力方法)。

对于一个完整的domChange，间隔可能是一个过度杀死。假设您需要存储整个文档的当前状态，并检查每个元素的每个属性是否相同。

也许如果您只对元素及其顺序感兴趣(如您在问题中提到的)，getElementsByTagName("*")可以工作。如果您添加一个元素，删除一个元素，替换元素或更改文档的结构，这将自动触发。

我写了一个概念证明:

(function (window) {
    var last = +new Date();
    var delay = 100; // default delay

    // Manage event queue
    var stack = [];

    function callback() {
        var now = +new Date();
        if (now - last > delay) {
            for (var i = 0; i < stack.length; i++) {
                stack[i]();
            }
            last = now;
        }
    }

    // Public interface
    var onDomChange = function (fn, newdelay) {
        if (newdelay) delay = newdelay;
        stack.push(fn);
    };

    // Naive approach for compatibility
    function naive() {

        var last = document.getElementsByTagName('*');
        var lastlen = last.length;
        var timer = setTimeout(function check() {

            // get current state of the document
            var current = document.getElementsByTagName('*');
            var len = current.length;

            // if the length is different
            // it's fairly obvious
            if (len != lastlen) {
                // just make sure the loop finishes early
                last = [];
            }

            // go check every element in order
            for (var i = 0; i < len; i++) {
                if (current[i] !== last[i]) {
                    callback();
                    last = current;
                    lastlen = len;
                    break;
                }
            }

            // over, and over, and over again
            setTimeout(check, delay);

        }, delay);
    }

    //
    //  Check for mutation events support
    //

    var support = {};

    var el = document.documentElement;
    var remain = 3;

    // callback for the tests
    function decide() {
        if (support.DOMNodeInserted) {
            window.addEventListener("DOMContentLoaded", function () {
                if (support.DOMSubtreeModified) { // for FF 3+, Chrome
                    el.addEventListener('DOMSubtreeModified', callback, false);
                } else { // for FF 2, Safari, Opera 9.6+
                    el.addEventListener('DOMNodeInserted', callback, false);
                    el.addEventListener('DOMNodeRemoved', callback, false);
                }
            }, false);
        } else if (document.onpropertychange) { // for IE 5.5+
            document.onpropertychange = callback;
        } else { // fallback
            naive();
        }
    }

    // checks a particular event
    function test(event) {
        el.addEventListener(event, function fn() {
            support[event] = true;
            el.removeEventListener(event, fn, false);
            if (--remain === 0) decide();
        }, false);
    }

    // attach test events
    if (window.addEventListener) {
        test('DOMSubtreeModified');
        test('DOMNodeInserted');
        test('DOMNodeRemoved');
    } else {
        decide();
    }

    // do the dummy test
    var dummy = document.createElement("div");
    el.appendChild(dummy);
    el.removeChild(dummy);

    // expose
    window.onDomChange = onDomChange;
})(window);

用法:

onDomChange(function(){ 
    alert("The Times They Are a-Changin'");
});

这适用于IE 5.5+， FF 2+， Chrome, Safari 3+和Opera 9.6+

MutationObserver = window.MutationObserver || window.WebKitMutationObserver;

var observer = new MutationObserver(function(mutations, observer) {
    // fired when a mutation occurs
    console.log(mutations, observer);
    // ...
});

// define what element should be observed by the observer
// and what types of mutations trigger the callback
observer.observe(document, {
  subtree: true,
  attributes: true
  //...
});

完整解释:https://stackoverflow.com/a/11546242/6569224

8年后，这是我使用MutationObserver和RxJS的解决方案

observeDOMChange(document.querySelector('#dom-changes-here'))
  .subscribe(val => log('DOM-change detected'));

与其他方法的主要区别是在DOM更改时触发CustomEvent，并通过以下特性侦听事件的恢复以有效地执行用户逻辑;

撤消连续的DOM更改，以防止执行过多 在给定的时间后停止观看 在停止监视DOM更改后删除事件侦听器/订阅者 观察一个框架(比如Angular)中发生的DOM变化是很有用的

import { fromEvent, timer} from 'rxjs';
import { debounceTime, takeUntil, tap } from 'rxjs/operators';

function observeDOMChange(el, options={}) {
  options = Object.assign({debounce: 100, expires: 2000}, options);

  const observer = new MutationObserver(list =>  {
    el.dispatchEvent(new CustomEvent('dom-change', {detail: list}));
  });
  observer.observe(el, {attributes: false, childList: true, subtree: true });

  let pipeFn;
  if (options.expires) {
    setTimeout(_ => observer.disconnect(), options.expires);
    pipeFn = takeUntil(timer(options.expires));
  } else {
    pipeFn = tap(_ => _); 
  }

  return fromEvent(el, 'dom-change')
    .pipe(pipeFn, debounceTime(options.debounce));
}

在stackblitz演示。

或者你可以简单地创建你自己的事件，到处运行

 $("body").on("domChanged", function () {
                //dom is changed 
            });


 $(".button").click(function () {

          //do some change
          $("button").append("<span>i am the new change</span>");

          //fire event
          $("body").trigger("domChanged");

        });

完整的示例 http://jsfiddle.net/hbmaam/Mq7NX/