原生js封装添加class,删除class的实例

function addClass(ele,cName) {
 var arr = ele.className.split(' ').concat(cName.split(" "));
 for(var i=0;i<arr.length;i++){
  for(var k=arr.length-1;k>i;k--){
   (arr[k]==="")&&arr.splice(k,1);
   (arr[i]===arr[k])&&arr.splice(k,1);
  }
 }
 ele.className = arr.join(" ");
}

function removeClass(ele,cName) {
 var arr1 = ele.className.split(' ');
 var arr2 = cName.split(" ");
 for(var i=0;i<arr2.length;i++)for(var j=arr1.length-1;j>=0;j--)(arr2[i]===arr1[j])&&arr1.splice(j,1)
 ele.className = arr1.join(" ")
}