JavaScript 系列二：第6課 ── 讀取與修改 DOM 元素的 style

by max002215

HTML

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>Document</title>

</head>
<body>
  <div id="app"></div>
  <input type="text" placeholder="請輸入代辦事項" id="text1">
  <select id="urgent" onchange="inputcolor()">
  <option value="none" selected disabled hidden>事項分類</option>
    <option value="normal">普通</option>
    <option value="important">重要</option>
    <option value="emergent">緊急</option>
  </select>
  <button type="button"onclick="to_do_list()">新增</button>
  <ul id="first_list">
  <li>
    <span>倒垃圾</span>
  </li>
  <li>
    <span>繳電話費</span>
  </li>
  <li>
    <span>採買本週食材</span>
  </li>
</ul>
<button type="button" id="export_btn">匯出</button>
</body>
</html>

CSS

.important {
  color: orange;
}
.emergent {
    color: red;
}
.normal {
  color: green;
}
.text_normal{
  color:green;
  font-weight: 500;
}
.text_important{
  color:orange;
  font-weight: 500;
}
.text_emergent{
  color:red;
  font-weight: 500;
}

JavaScript

function to_do_list() {
  let list = document.getElementById("text1").value;
  let FirstList = document.getElementById("first_list");
  let listUrgent = document.getElementById("urgent");
  let list1 = document.createElement('li');
  let list2 = document.createElement('span');
  let btn1 = document.createElement('button');
  let btn2 = document.createElement('button');
  let listUrgentIndex = listUrgent.selectedIndex
  let listUrgenValue = listUrgent.options[listUrgentIndex].value
  let list3 = list2.textContent = list;
  btn1.textContent = "刪除";
  btn2.textContent = "已完成";
  FirstList.append(list1);
  list1.append(list2, btn2, btn1);
  btn1.onclick = hello;

  let div1 = document.createElement('div');
  list2.append(div1);
  div1.textContent = "(已完成)";
  div1.style.display = "none"
  btn2.onclick = Finish;
  if (listUrgenValue == "normal") {
    list1.className = list1.className + "normal";
  } else if (listUrgenValue == "important") {
    list1.className = list1.className + "important";
  } else {
    list1.className = list1.className + "emergent";
  }
  /* list2.append(list3);
   */
  /* console.log(list) */
  /* console.log(FirstList) */
  /* console.log(list1) */
  /* console.log(list2);
  console.log(list3); */

  function Finish() {
    if (div1.style.display === "none") {
      div1.style.display = "inline"
      btn2.textContent = "標示未完成";
    } else {
      div1.style.display = "none"
     btn2.textContent = "標示已完成";

    }
  }

}
let exportBtn = document.getElementById("export_btn");
exportBtn.onclick = exportList;

function exportList() {
  //先抓到主要清單子層
  let list = document.getElementById("first_list").children;
  //設立空字串
  let text = "";
  //設立號碼
  let num = 1;
  //迴圈開始 item=迴圈變數名 of=把剛剛的抓到的子層陣列塞到迴圈變數裡面 list剛剛抓到子層的變數名
  for (let item of list) {
    let itemclass = item.className;
    if (itemclass == "important") { //內容為空字串=空字串+號碼.轉成字串方法+點字串+迴圈變數.子層[陣列序號].文字內容+空字串
      text = text + num.toString() + "." + "*" + item.children[0].textContent + "*";
  ...