我想执行一个函数时,一些div或输入被添加到html。 这可能吗?

例如,添加了一个文本输入,然后应该调用函数。


当前回答

下面的例子改编自Mozilla Hacks的博客文章,并使用MutationObserver。

// Select the node that will be observed for mutations
var targetNode = document.getElementById('some-id');

// Options for the observer (which mutations to observe)
var config = { attributes: true, childList: true };

// Callback function to execute when mutations are observed
var callback = function(mutationsList) {
    for(var mutation of mutationsList) {
        if (mutation.type == 'childList') {
            console.log('A child node has been added or removed.');
        }
        else if (mutation.type == 'attributes') {
            console.log('The ' + mutation.attributeName + ' attribute was modified.');
        }
    }
};

// Create an observer instance linked to the callback function
var observer = new MutationObserver(callback);

// Start observing the target node for configured mutations
observer.observe(targetNode, config);

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

浏览器支持:Chrome 18+, Firefox 14+, IE 11+, Safari 6+

其他回答

在2022年发现了这个问题的解决方案。

我们已经看到了不同的解决方案,主要涉及MutationObserver。

如果有人想记录DOM更改并存储它们以便一段时间后重播,他们可以使用rrweb

编辑:

再举个例子,下面是一些提示:

rrweb您可以通过CDN或npm使用

让我们以CDN为例来记录DOM更改事件:

步骤1:只需在<HTML><head>标签中包含以下脚本标签

<script src="https://cdn.jsdelivr.net/npm/rrweb@2.0.0-alpha.2/dist/rrweb-all.js" crossorigin="anonymous"></script> .js

步骤2:并在代码中添加以下代码以捕获rrweb生成的事件。

<script>
var events = [];
rrweb.record({
    emit(event) {
       events.push(event);
       // you can store this event anywhere and you can replay them later. ex: some JSON file, or DB
    }
});

</script>

这个例子主要用于记录任何web应用程序的事件。

如需详细了解(如何录制/回放),请参阅rrweb文档。

重播的例子:

这是为了调试,但添加在这里,以便任何人都可以检查重放的一面:

重复的例子

到目前为止,使用最小代码的终极方法:

(IE11+, FF, Webkit)

使用MutationObserver并退回到已弃用的 突变事件(如果需要的话): (下面的示例仅用于涉及追加或删除节点的DOM更改)

var observeDOM = (function(){ var MutationObserver = window.MutationObserver || window.WebKitMutationObserver; return function( obj, callback ){ if( !obj || obj.nodeType !== 1 ) return; if( MutationObserver ){ // define a new observer var mutationObserver = new MutationObserver(callback) // have the observer observe for changes in children mutationObserver.observe( obj, { childList:true, subtree:true }) return mutationObserver } // browser support fallback else if( window.addEventListener ){ obj.addEventListener('DOMNodeInserted', callback, false) obj.addEventListener('DOMNodeRemoved', callback, false) } } })() //------------< DEMO BELOW >---------------- // add item var itemHTML = "<li><button>list item (click to delete)</button></li>", listElm = document.querySelector('ol'); document.querySelector('body > button').onclick = function(e){ listElm.insertAdjacentHTML("beforeend", itemHTML); } // delete item listElm.onclick = function(e){ if( e.target.nodeName == "BUTTON" ) e.target.parentNode.parentNode.removeChild(e.target.parentNode); } // Observe a specific DOM element: observeDOM( listElm, function(m){ var addedNodes = [], removedNodes = []; m.forEach(record => record.addedNodes.length & addedNodes.push(...record.addedNodes)) m.forEach(record => record.removedNodes.length & removedNodes.push(...record.removedNodes)) console.clear(); console.log('Added:', addedNodes, 'Removed:', removedNodes); }); // Insert 3 DOM nodes at once after 3 seconds setTimeout(function(){ listElm.removeChild(listElm.lastElementChild); listElm.insertAdjacentHTML("beforeend", Array(4).join(itemHTML)); }, 3000); <button>Add Item</button> <ol> <li><button>list item (click to delete)</button></li> <li><button>list item (click to delete)</button></li> <li><button>list item (click to delete)</button></li> <li><button>list item (click to delete)</button></li> <li><em>&hellip;More will be added after 3 seconds&hellip;</em></li> </ol>

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

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();

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。