js点击页面空白处，实现操作

通过为window绑定click时间即可实现
比如制作一个模态框，点在模态框上实现关闭模态框

<button onclick="document.getElementById('id01').style.display='block'">注册</button>

<div id="id01" class="modal">
  <form class="modal-content animate ">
    <div class="container">
      <label><b>Email</b></label>
      <input type="text" placeholder="Enter Email" name="email" required>
  </form>
</div>

input[type=text] {
    width: 100%;
    padding: 12px 20px;
    margin: 8px 0;
    display: inline-block;
    border: 1px solid #ccc;
    box-sizing: border-box;
}
button {
    background-color: #4CAF50;
    color: white;
    padding: 14px 20px;
    margin: 8px 0;
    border: none;
    cursor: pointer;
}
.container {
    padding: 16px;
}
.modal {
    display: none;
    position: fixed;
    z-index: 1;
    left: 0;
    top: 0;
    width: 100%; 
    height: 100%; 
    overflow: auto; 
    background-color: rgba(0,0,0,0.4); 
    padding-top: 60px;
}
.modal-content {
    background-color: #fefefe;
    margin: 5% auto 15% auto; 
    border: 1px solid #888;
    width: 80%; 
}
.animate {
    -webkit-animation: animatezoom 0.6s;
    animation: animatezoom 0.6s
}

@-webkit-keyframes animatezoom {
    from {-webkit-transform: scale(0)} 
    to {-webkit-transform: scale(1)}
}
    
@keyframes animatezoom {
    from {transform: scale(0)} 
    to {transform: scale(1)}
}

// 获取模型
var modal = document.getElementById('id01');

// 鼠标点击模型外区域关闭登录框
window.onclick = function(event) {
  	console.log(event)
    if (event.target == modal) {
        modal.style.display = "none";
    }
}