这个 javasScript 排序函数是否正确?
Is this javasScript sorting function correct?
我是 javaScript 初学者。此功能有效,并允许我通过单击按钮按上升和下降排序列表,但我想知道它是否正确编写或者是否可以简化或以不同方式编写。提前致谢。
index.html
<p id="sort">Sort</p>
<ul>
<li>Phosphorus</li>
<li>Polonium</li>
<li>Radium</li>
<li>Fluorine</li>
<li>Iron</li>
<li>Hydrogen</li>
<li>Germanium</li>
<li>Mercury</li>
<li>Actinium</li>
<li>Barium</li>
<li>Calcium</li>
<li>Cadmium</li>
</ul>
<script src="main.js"></script>
main.js
const sortButton = document.querySelector("#sort");
let counter = 0;
eventListeners();
function eventListeners() {
sortButton.addEventListener("click", sortList);
}
function sortList() {
const elementsList = new Array();
const elements = document.querySelectorAll("ul li");
for (const element of elements) {
elementsList.push(element.textContent);
}
const ul = document.querySelector("ul");
ul.innerHTML = "";
if (counter % 2 === 0) {
const orderedList = elementsList.sort();
for (let i = 0; i < orderedList.length; i++) {
const li = document.createElement("li");
li.innerHTML = orderedList[i];
ul.appendChild(li);
}
counter++;
} else {
const orderedList = elementsList.reverse();
for (let i = 0; i < orderedList.length; i++) {
const li = document.createElement("li");
li.innerHTML = orderedList[i];
ul.appendChild(li);
}
counter++;
}
}
您不必清除 ul 的 innerHTML,甚至不必使用 innerHTML
element.appendChild 将移动现有元素 - 如下所示
const sortButton = document.querySelector("#sort");
let counter = 0;
eventListeners();
function eventListeners() {
sortButton.addEventListener("click", sortList);
}
function sortList() {
const elementsList = Array.from(document.querySelectorAll("ul li"));
const ul = document.querySelector("ul");
elementsList.sort(({textContent:a}, {textContent:b})=>(counter%2?-1:1)*a.localeCompare(b))
.forEach(el => ul.appendChild(el));
counter++;
}
<p id="sort">Sort</p>
<ul>
<li>Phosphorus</li>
<li>Polonium</li>
<li>Radium</li>
<li>Fluorine</li>
<li>Iron</li>
<li>Hydrogen</li>
<li>Germanium</li>
<li>Mercury</li>
<li>Actinium</li>
<li>Barium</li>
<li>Calcium</li>
<li>Cadmium</li>
</ul>
在 Es2015 中(即老派的 javascirpt)——这个函数看起来像:
function sortList() {
var elementsList = Array.from(document.querySelectorAll("ul li"));
var ul = document.querySelector("ul");
elementsList.sort(function (_ref, _ref2) {
var a = _ref.textContent;
var b = _ref2.textContent;
return (counter % 2 ? -1 : 1) * a.localeCompare(b);
}).forEach(function (el) {
return ul.appendChild(el);
});
counter++;
}
我是 javaScript 初学者。此功能有效,并允许我通过单击按钮按上升和下降排序列表,但我想知道它是否正确编写或者是否可以简化或以不同方式编写。提前致谢。
index.html
<p id="sort">Sort</p>
<ul>
<li>Phosphorus</li>
<li>Polonium</li>
<li>Radium</li>
<li>Fluorine</li>
<li>Iron</li>
<li>Hydrogen</li>
<li>Germanium</li>
<li>Mercury</li>
<li>Actinium</li>
<li>Barium</li>
<li>Calcium</li>
<li>Cadmium</li>
</ul>
<script src="main.js"></script>
main.js
const sortButton = document.querySelector("#sort");
let counter = 0;
eventListeners();
function eventListeners() {
sortButton.addEventListener("click", sortList);
}
function sortList() {
const elementsList = new Array();
const elements = document.querySelectorAll("ul li");
for (const element of elements) {
elementsList.push(element.textContent);
}
const ul = document.querySelector("ul");
ul.innerHTML = "";
if (counter % 2 === 0) {
const orderedList = elementsList.sort();
for (let i = 0; i < orderedList.length; i++) {
const li = document.createElement("li");
li.innerHTML = orderedList[i];
ul.appendChild(li);
}
counter++;
} else {
const orderedList = elementsList.reverse();
for (let i = 0; i < orderedList.length; i++) {
const li = document.createElement("li");
li.innerHTML = orderedList[i];
ul.appendChild(li);
}
counter++;
}
}
您不必清除 ul 的 innerHTML,甚至不必使用 innerHTML
element.appendChild 将移动现有元素 - 如下所示
const sortButton = document.querySelector("#sort");
let counter = 0;
eventListeners();
function eventListeners() {
sortButton.addEventListener("click", sortList);
}
function sortList() {
const elementsList = Array.from(document.querySelectorAll("ul li"));
const ul = document.querySelector("ul");
elementsList.sort(({textContent:a}, {textContent:b})=>(counter%2?-1:1)*a.localeCompare(b))
.forEach(el => ul.appendChild(el));
counter++;
}
<p id="sort">Sort</p>
<ul>
<li>Phosphorus</li>
<li>Polonium</li>
<li>Radium</li>
<li>Fluorine</li>
<li>Iron</li>
<li>Hydrogen</li>
<li>Germanium</li>
<li>Mercury</li>
<li>Actinium</li>
<li>Barium</li>
<li>Calcium</li>
<li>Cadmium</li>
</ul>
在 Es2015 中(即老派的 javascirpt)——这个函数看起来像:
function sortList() {
var elementsList = Array.from(document.querySelectorAll("ul li"));
var ul = document.querySelector("ul");
elementsList.sort(function (_ref, _ref2) {
var a = _ref.textContent;
var b = _ref2.textContent;
return (counter % 2 ? -1 : 1) * a.localeCompare(b);
}).forEach(function (el) {
return ul.appendChild(el);
});
counter++;
}