看到这个题目,立马想到的就是element.classList.contains()和$(element).hasClass()方法。 但是,在一些低版本浏览器中,classList无法使用,这个时候就可以自己实现类似jQuery的hasClass()函数。 classList的兼容性 假如我们 有如下测试元素 1 简单正则匹配法 最开始我们找到的方法如下,即使用正则判断单词边界的方式判...
functionfindParentElement(element,className){if(!element)returnnull;if(element.classList.contains(className)){returnelement;}else{returnfindParentElement(element.parentNode,className);}}constchildElement=document.getElementById('child');constparentElement=findParentElement(childElement,'parent');console.log(...
testElement.classList.add("c1", "c2"); // Polyfill for IE 10/11 and Firefox <26, where classList.add and // classList.remove exist but support only one argument at a time. if (!testElement.classList.contains("c2")) { var createMethod = function(method) { var original = DOMToken...
因此,Element 对象定义了一个 classList 属性,允许您将 class 属性视为列表。classList 属性的值是一个可迭代的类似数组的对象。尽管属性的名称是 classList,但它更像是一组类,并定义了 add()、remove()、contains() 和toggle() 方法: 代码语言:javascript 复制 // When we want to let the user know that...
constructor() Creates and initialize objects created within a class Classes constructor Returns the function that created the Array object's prototype Array, Boolean, Date, Number, RegExp contains() Returns true if a node is a descendant of a node, otherwise false Element contentEditable Sets or ...
nearBox.classList.add('check'); leftClick(nearBox); } } } } } } } function rightClick(dom){ if(dom.classList.contains('num')){ return; } dom.classList.toggle('flag'); if(dom.classList.contains('isLei') &&dom.classList.contains('flag')){ ...
With understanding, we can check if the current user is logged in with JavaScript simply, like this: if ( document.body.classList.contains( 'logged-in' ) ) { console.log( 'The user is logged in' ); } else { console.log( 'The user is not logged in' ); ...
document.addEventListener("click",function(e){constel=e.target;if(!el.classList.contains("track-click"))return;client.click({query:el.getAttribute("data-query"),documentId:el.getAttribute("data-document-id"),requestId:el.getAttribute("data-request-id"),tags:[el.getAttribute("data-tag")]})...
35 if (!document.querySelector("#check").checked) { 36 document.querySelector("#error").classList.remove("hidden"); 37 } 38 }, 39 }).render("#paypal-button-container"); 40 41 42 For cases when you need asynchronous validation, see asynchronous validation. paypal.Buttons()....
if (!event.target.matches('.dropbtn')) { var dropdowns = document.getElementsByClassName("dropdown-content"); var i; for (i = 0; i < dropdowns.length; i++) { var openDropdown = dropdowns[i]; if (openDropdown.classList.contains('show')) { openDropdown.classList.remove('show...