[js] 获取页面上所有的 className 并且去重

[VaJoy]

最终得到一个数组
实现方式多，但要尽量写的好看一点哦~

[li2568261]

let allClassName = ()=>{
			let className = new Set();
			let hasClassEl = document.querySelectorAll('[class]');
			[].forEach.call(hasClassEl,(v,i)=>{
				let classArr = v.getAttribute("class").split(' ');
				classArr.map(name => className.add(name));
			})
			return [...className]
		}

[akaxiaok]

function getClass() {
    let classes = [];
    Array.from(document.querySelectorAll('[class]')).forEach(node=> {
            classes = classes.concat(node.className.split(' '));
    });
    return Array.from(new Set(classes));
}

[decadeheart]

    function getClassNames(){
        var classes=document.querySelectorAll('[class]'),i;
        var classNames=[];
        for(i=0;i<classes.length;i++){
            classNames=classNames.concat(classes[i].className.split(''));
        }
        var classArray=Array.from(new Set(classNames))
        return classArray;
    }  

[aolinpk]

var classes = document.querySelectorAll('[class]');
classes = Array.prototype.slice.call(classes,0); 
var classNames = [];
classes.forEach(function(v,k) {
    classNames = classNames.concat(classes[k].className.split(''));
})
classNames = new Set(classNames);

[ysjhnuitanfei]

有没有大神带带我学前端

[Jiasm]

[...new Set(Array.from(document.querySelectorAll('[class]')).map(({className: c}) => c).join(' ').split(' '))]

[uinz]

function allClassName() {
  const classNames = [...document.querySelectorAll("[class]")].reduce(
    (list, node) => [...list, ...node.classList.values()],
    []
  );
  return [...new Set(classNames)];
}