JS原生實現元素的拖拽
頁面樣式
<!DOCTYPE html>
<html>
<head lang="en">
<meta charset="UTF-8">
<title></title>
<style>
.login-header {
width: 100%;
text-align: center;
height: 30px;
font-size: 24px;
line-height: 30px;
}
ul,
li,
ol,
dl,
dt,
dd,
div,
p,
span,
h1,
h2,
h3,
h4,
h5,
h6,
a {
padding: 0px;
margin: 0px;
}
.login {
width: 512px;
position: absolute;
border: #ebebeb solid 1px;
height: 280px;
left: 50%;
right: 50%;
background: #ffffff;
box-shadow: 0px 0px 20px #ddd;
z-index: 9999;
margin-left: -250px;
margin-top: 140px;
display: none;
}
.login-title {
width: 100%;
margin: 10px 0px 0px 0px;
text-align: center;
line-height: 40px;
height: 40px;
font-size: 18px;
position: relative;
cursor: move;
-moz-user-select: none;
/*火狐*/
-webkit-user-select: none;
/*webkit瀏覽器*/
-ms-user-select: none;
/*IE10*/
-khtml-user-select: none;
/*早期瀏覽器*/
user-select: none;
}
.login-input-content {
margin-top: 20px;
}
.login-button {
width: 50%;
margin: 30px auto 0px auto;
line-height: 40px;
font-size: 14px;
border: #ebebeb 1px solid;
text-align: center;
}
.login-bg {
width: 100%;
height: 100%;
position: fixed;
top: 0px;
left: 0px;
background: #000000;
filter: alpha(opacity=30);
-moz-opacity: 0.3;
-khtml-opacity: 0.3;
opacity: 0.3;
display: none;
}
a {
text-decoration: none;
color: #000000;
}
.login-button a {
display: block;
}
.login-input input.list-input {
float: left;
line-height: 35px;
height: 35px;
width: 350px;
border: #ebebeb 1px solid;
text-indent: 5px;
}
.login-input {
overflow: hidden;
margin: 0px 0px 20px 0px;
}
.login-input label {
float: left;
width: 90px;
padding-right: 10px;
text-align: right;
line-height: 35px;
height: 35px;
font-size: 14px;
}
.login-title span {
position: absolute;
font-size: 12px;
right: -20px;
top: -30px;
background: #ffffff;
border: #ebebeb solid 1px;
width: 40px;
height: 40px;
border-radius: 20px;
}
</style>
</head>
<body>
<div class="login-header"><a id="link" href="javascript:void(0);">點擊，彈出登錄框</a></div>
<div id="login" class="login">
<div id="title" class="login-title">登錄會員
<span><a id="closeBtn" href="javascript:void(0);" class="close-login">關閉</a></span></div>
<div class="login-input-content">
<div class="login-input">
<label>用戶名：</label>
<input type="text" placeholder="請輸入用戶名" name="info[username]" id="username" class="list-input">
</div>
<div class="login-input">
<label>登錄密碼：</label>
<input type="password" placeholder="請輸入登錄密碼" name="info[password]" id="password" class="list-input">
</div>
</div>
<div id="loginBtn" class="login-button"><a href="javascript:void(0);" id="login-button-submit">登錄會員</a></div>
</div>
<!--登錄框-->
<div id="bg" class="login-bg"></div>
<!--遮擋層-->
</body>
</html>
腳本文件
/**
* 獲取指定標籤對象
* @param id 標籤的id屬性值
* @returns {Element}根據id屬性值返回指定標籤對象
*/
function my$(id) {
return document.getElementById(id);
}
//點擊超鏈接彈出登錄框,點擊頁面的任何位置都可以關閉登錄框
my$("link").onclick = function (e) {
my$("login").style.display = "block";
my$("bg").style.display = "block";
e.stopPropagation();
console.log('出現');
};
//獲取關閉,註冊點擊事件,隱藏登錄框和遮擋層
my$("closeBtn").onclick = function () {
my$("login").style.display = "none";
my$("bg").style.display = "none";
};
//按下鼠標,移動鼠標,移動登錄框
my$("title").onmousedown = function (e) {
//獲取此時的可視區域的橫座標-此時登錄框距離左側頁面的橫座標
var spaceX = e.clientX - my$("login").offsetLeft;
var spaceY = e.clientY - my$("login").offsetTop;
// 移動事件
document.onmousemove = function (e) {
// 獲取頁面寬高
var bodyW = document.documentElement.clientWidth
var bodyH = document.documentElement.clientHeight
// 獲取盒子寬高
var loginH = my$('login').offsetHeight
var loginW = my$('login').offsetWidth
// 獲取關閉按鈕多出來的寬高,只要一半就行
var btnH = my$('closeBtn').parentNode.offsetHeight / 2
var btnW = my$('closeBtn').parentNode.offsetWidth / 2
// 新的可視區域的橫座標-spaceX====>新的值--->登錄框的left屬性
// 同時對可移動範圍進行限制
var loginX, loginY
// 限制橫向區域移動範圍
if (e.clientX - spaceX <= 0) {
loginX = 0
} else if (e.clientX - spaceX > 0 && e.clientX - spaceX <= bodyW - loginW - btnW) {
loginX = e.clientX - spaceX
} else {
loginX = bodyW - loginW - btnW
}
// 限制縱向區域移動範圍
if (e.clientY - spaceY <= btnH) {
loginY = btnH
} else if (e.clientY - spaceY > 0 && e.clientY - spaceY <= bodyH - loginH) {
loginY = e.clientY - spaceY
} else {
loginY = bodyH - loginH
}
// 加上外邊距就實現點哪兒是哪兒了
var x = loginX + 250
var y = loginY - 140
my$('login').style.left = x + 'px'
my$('login').style.top = y + 'px'
}
}
document.onmouseup = function () {
document.onmousemove = null; //當鼠標擡起的時候,把鼠標移動事件幹掉
};
示例演示
