外部點擊下拉選單未關閉

我創建了一個下拉選單。但是當我單擊外部保持下拉選單打開時，我遇到了一個問題，下拉選單不會關閉。我嘗試添加許多 javascript 代碼，但最后我做不到。請有人幫我解決這個問題。我在下面給出了我的專案代碼。我只需要通過此 JS 代碼關閉單擊下拉選單之外的此功能。

function toggleDropDown(id) {
    document.querySelectorAll('.dropdown-content').forEach(el => el.id === id ? el.classList.toggle('show') : el.classList.remove("show"));
}

  
body{  
  font-family: Arial, Helvetica, sans-serif;
}

.navbar {
  overflow: hidden;
  background-color: #333;
  display:flex;
  align-items:center;
  justify-content: space-between;
}

.navbar a {
  float: left;
  font-size: 16px;
  color: white;
  text-align: center;
  padding: 14px 16px;
  text-decoration: none;
}
.dropdown{
display:inline;
}
.dropdown .dropbtn {
  font-size: 16px;  
  border: none;
  outline: none;
  color: white;
  padding: 14px 16px;
  background-color: inherit;
  font-family: inherit;
  margin: 0;
}

.dropdown-content {
  display: none;
  position: absolute;
  background-color: #f9f9f9;
  min-width: 260px;
  box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2);
  z-index: 1;
}

.dropdown-content a {
  float: none;
  color: black;
  padding: 12px 16px;
  text-decoration: none;
  display: block;
  text-align: left;
}

.dropdown-content a:hover {
  background-color: #ddd;
}
.show{display:block;}

<div class="navbar">
  <a href="#home">Home</a>
  <a href="#news">News</a>
  <div class="dropdown">
    <button class="dropbtn" onclick="toggleDropDown('div1')">Dropdown1 
      <i class="fa fa-caret-down"></i>
    </button>
    <div class="dropdown-content" id=div1>
      <p>Div1 dropdown</p>
    </div>
     <div class="dropdown">
    <button class="dropbtn" onclick="toggleDropDown('div2')">Dropdown2 
      <i class="fa fa-caret-down"></i>
    </button>
    <div class="dropdown-content" id=div2>
      <p>Div2 dropdown</p>
    </div>
  </div> 
</div>

uj5u.com熱心網友回復：

一種方法是在檔案上添加一個 eventListener。然后您檢查已單擊的內容，如果它涉及您的下拉選單，則什么也不做，如果它不涉及您的下拉選單，則關閉下拉選單。

此示例使用closest()which 將向上單擊元素的父元素以嘗試找到具有 class 的元素dropdown。如果它找到一個（非空），那么我們知道我們不想關閉下拉選單，因為用戶正在與它互動。所有其他情況將關閉下拉選單。

document.addEventListener('click', (e) => {

  // cases where we want to close the dropdown
  if (e.target.closest(".dropdown") === null) {
    document.querySelectorAll('.dropdown-content').forEach(el => el.classList.remove("show"));
  }

});

function toggleDropDown(id) {
  document.querySelectorAll('.dropdown-content').forEach(el => el.id === id ? el.classList.toggle('show') : el.classList.remove("show"));
}

body {
  font-family: Arial, Helvetica, sans-serif;
}

.navbar {
  overflow: hidden;
  background-color: #333;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.navbar a {
  float: left;
  font-size: 16px;
  color: white;
  text-align: center;
  padding: 14px 16px;
  text-decoration: none;
}

.dropdown {
  display: inline;
}

.dropdown .dropbtn {
  font-size: 16px;
  border: none;
  outline: none;
  color: white;
  padding: 14px 16px;
  background-color: inherit;
  font-family: inherit;
  margin: 0;
}

.dropdown-content {
  display: none;
  position: absolute;
  background-color: #f9f9f9;
  min-width: 260px;
  box-shadow: 0px 8px 16px 0px rgba(0, 0, 0, 0.2);
  z-index: 1;
}

.dropdown-content a {
  float: none;
  color: black;
  padding: 12px 16px;
  text-decoration: none;
  display: block;
  text-align: left;
}

.dropdown-content a:hover {
  background-color: #ddd;
}

.show {
  display: block;
}

<div class="navbar">
  <a href="#home">Home</a>
  <a href="#news">News</a>
  <div class="dropdown">
    <button class="dropbtn" onclick="toggleDropDown('div1')">Dropdown1 
      <i class="fa fa-caret-down"></i>
    </button>
    <div class="dropdown-content" id="div1">
      <p>Div1 dropdown</p>
    </div>
    <div class="dropdown">
      <button class="dropbtn" onclick="toggleDropDown('div2')">Dropdown2 
      <i class="fa fa-caret-down"></i>
    </button>
      <div class="dropdown-content" id="div2">
        <p>Div2 dropdown</p>
      </div>
    </div>
  </div>
</div>

uj5u.com熱心網友回復：

也許這個不是最好和可靠的解決方案，但在沒有 JS 的情況下作業，將能夠幫助您：

body {
  font-family: Arial, Helvetica, sans-serif;
}

.navbar {
  overflow: hidden;
  background-color: #333;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.navbar a {
  float: left;
  font-size: 16px;
  color: white;
  text-align: center;
  padding: 14px 16px;
  text-decoration: none;
}

.dropdown {
  display: inline;
}

.dropdown .dropbtn {
  font-size: 16px;
  border: none;
  outline: none;
  color: white;
  padding: 14px 16px;
  background-color: inherit;
  font-family: inherit;
  margin: 0;
}

.dropdown-content {
  display: none;
  position: absolute;
  background-color: #f9f9f9;
  min-width: 260px;
  box-shadow: 0px 8px 16px 0px rgba(0, 0, 0, 0.2);
  z-index: 1;
}

.dropdown-content a {
  float: none;
  color: black;
  padding: 12px 16px;
  text-decoration: none;
  display: block;
  text-align: left;
}

.dropdown-content a:hover {
  background-color: #ddd;
}

/*
  added to CSS
*/
.dropbtn   .dropdown-content:hover, .dropbtn:focus   .dropdown-content {
    display: block;
    pointer-events: all !important;
}

<div class="navbar">
  <a href="#home">Home</a>
  <a href="#news">News</a>
  <div class="dropdown">
    <button class="dropbtn">Dropdown1 
      <i class="fa fa-caret-down"></i>
    </button>
    <div class="dropdown-content">
      <p>Div1 dropdown</p>
    </div>
    <div class="dropdown">
      <button class="dropbtn">Dropdown2 
      <i class="fa fa-caret-down"></i>
    </button>
      <div class="dropdown-content">
        <p>Div2 dropdown</p>
      </div>
    </div>
  </div>

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