CSS - 浮动
2019-04-04 本文已影响0人
Hyso
浮动的特点
- 浮动可以让多个块元素在同一行显示
浮动前：
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<style>
.box1 {
width: 100px;
height: 100px;
background-color: yellow;
}
.box2 {
width: 100px;
height: 100px;
background-color: red;
}
</style>
</style>
</style>
</head>
<body>
<div class="box1"></div>
<div class="box2"></div>
</body>
</html>
浮动后：
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<style>
.box1 {
width: 100px;
height: 100px;
float: left;
background-color: yellow;
}
.box2 {
width: 100px;
height: 100px;
float: left;
background-color: red;
}
</style>
</style>
</style>
</head>
<body>
<div class="box1"></div>
<div class="box2"></div>
</body>
</html>
- 浮动的元素排列在其父级元素的左上角或右上角（float: right）
左上角（float: left）：
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<style>
.box {
width: 300px;
height: 300px;
background-color: yellow;
}
.box1 {
width: 100px;
height: 100px;
float: left;
background-color: red;
}
</style>
</style>
</style>
</head>
<body>
<div class="box">
<div class="box1"></div>
</div>
</body>
</html>
右上角（float: right）：
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<style>
.box {
width: 300px;
height: 300px;
background-color: yellow;
}
.box1 {
width: 100px;
height: 100px;
float: right;
background-color: red;
}
</style>
</style>
</style>
</head>
<body>
<div class="box">
<div class="box1"></div>
</div>
</body>
</html>
- 浮动可以让元素适应内容的宽度
浮动前：
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<style>
.box {
background-color: yellow;
}
</style>
</style>
</style>
</head>
<body>
<div class="box">123</div>
</body>
</html>
浮动后：
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<style>
.box {
float: left;
background-color: yellow;
}
</style>
</style>
</style>
</head>
<body>
<div class="box">123</div>
</body>
</html>
浮动案例
- 如下代码中，如何让3个元素靠网页右边排列，且第一个元素在最左边，第二个元素在中间，第三个元素在最右边
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<style>
.box1 {
width: 100px;
height: 100px;
background-color: yellow;
}
.box2 {
width: 100px;
height: 100px;
background-color: red;
}
.box3 {
width: 100px;
height: 100px;
background-color: green;
}
</style>
</style>
</style>
</head>
<body>
<div class="box1"></div>
<div class="box2"></div>
<div class="box3"></div>
</body>
</html>
解决方案：在3个元素外面套一个父元素，父元素向右浮动，3个子元素向左浮动
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<style>
.box_parent {
float: right;
}
.box1 {
width: 100px;
height: 100px;
float: left;
background-color: yellow;
}
.box2 {
width: 100px;
height: 100px;
float: left;
background-color: red;
}
.box3 {
width: 100px;
height: 100px;
float: left;
background-color: green;
}
</style>
</style>
</style>
</head>
<body>
<div class="box_parent">
<div class="box1"></div>
<div class="box2"></div>
<div class="box3"></div>
</div>
</body>
</html>
