JavaScript动态添加和删除类
这个问题在这里已经有了答案：
由于关注的分离，考虑使用onclick属性的替代方案可能是明智的。 以下内容允许您在工作时不必考虑JavaScript而改变HTML。
https://jsfiddle.net/gseh0wxc/2/
var getList = (selector) => [].slice.call(document.querySelectorAll(selector));
var paragraphs = getList("#divid p[id ^= 'p']");
paragraphs.forEach((paragraph, index) => {
paragraph.addEventListener('click', (e) => {
for (let i = 0; i < index; i++) {
paragraphs[i].classList.remove('active');
}
for (let i = index; i < paragraphs.length; i++) {
paragraphs[i].classList.add('active');
}
});
})
请试试这个代码
function test(object) {
var pid = object.id;
var id = parseInt(pid.split("")[1]);
console.log(id);
for (var i = 1; i <= id; i++) {
var element = document.getElementById("p"+i);
element.classList.add("active");
}
console.log(id+1);
for(var i = id+1; i <= 4; i++) {
var element = document.getElementById("p"+i);
element.classList.remove("active");
}
}
希望这可以帮助。
试试这个简单的方法，而不需要提取id号和所有，并用一个简单的循环。
function test(option) {
//this will select all p tags id starts with "p" inside div having id "divid" and return a array
var targetPTags = document.querySelectorAll("div#divid p[id^=p]")
var idx, flag=false;
//we are iterating over that array and taking each dom element in el
for(idx=0;idx<targetPTags.length;idx++) {
var el = targetPTags[idx];
if(flag) {
//do operation you want for after elements in el
} else if(option===el) {
flag=true; // we are making flag true when its the element that clicked and doing no operation
//do the operation you want for the element, may be the same as below operation in else
} else {
//do operation you want for before element in el
}
}
}