js--怎样去操作元素的样式类名

function hasClass(curEle,className){// if(curEle.className.indexOf(className)){//     return true;  使用indexOf是有问题的// }// return false;var reg = new RegExp("(^| +)"+className+"( +|$)")return reg.test(curEle.className);
    }

function addClass(curEle,className){//为了防止className传递进来的值包含多个样式类名，我们把传递进来的字符串按照一到多个空格拆分成数组中的每一项var ary = className.split(/ +/g);//循环数组，一项项的进行验证增加即可for(var i = 0;i<ary.length;i++){var curName = ary[i]if(!hasClass(curEle,curName)){// curEle.className += " " + className; //如果className类似于这样的"position bg"多个组合的，会出现重复问题curEle.className += " " + curName;
            }
        }
        
    }

function removeClass(curEle,className){var ary = className.split(/ +/g);for(var i = 0;i<ary.length;i++){var curName = ary[i]if(hasClass(curEle,curName)){var reg = new RegExp("(^| +)"+curName+"( +|$)","g");
                curEle.className = curEle.className.replace(reg," ")
            }
        }
    }