对这个问题最好的回答是使用margin-auto，但要使用它，你必须知道你的div的宽度在px或%。

CSS代码:

div{
    width:30%;
    margin-left:auto;
    margin-right:auto;
}

问题的标题和内容实际上是不同的，所以我将发布两个解决方案，使用Flexbox。

我猜在IE8和IE9完全被摧毁之前，Flexbox将取代/添加到当前的标准解决方案中;)

检查当前flexbox的浏览器兼容性表

单一的元素

.container { 显示:flex; justify-content:中心; ｝ < div class = "容器" > < img src = " http://placehold.it/100x100 " > < / div >

多个元素，但只以一个为中心

默认行为是flex-direction: row，将所有子项对齐在一行中。将其设置为flex-direction: column将有助于堆叠的行。

.container { display: flex; flex-direction: column; } .centered { align-self: center; } <div class="container"> <p>Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book. It has survived not only five centuries, but also the leap into electronic typesetting, remaining essentially unchanged. </p> <div class="centered"><img src="http://placehold.it/100x100"></div> <p>Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book. It has survived not only five centuries, but also the leap into electronic typesetting, remaining essentially unchanged. </p> </div>

你应该在父元素上使用position: relative和text-align: center，然后在你想居中的子元素上使用display: inline-block。这是一个简单的CSS设计模式，适用于所有主流浏览器。下面是一个示例或查看CodePen示例。

p { text-align: left; } .container { position: relative; display: block; text-align: center; } /* Style your object */ .object { padding: 10px; color: #ffffff; background-color: #556270; } .centerthis { display: inline-block; } <div class="container"> <p>Aeroplanigera Mi Psychopathologia Subdistinctio Chirographum Intuor Sons Superbiloquentia Os Sors Sesquiseptimus Municipatio Archipresbyteratus O Conclusio Compedagogius An Maius Septentrionarius Plas Inproportionabilit Constantinopolis Particularisticus.</p> <span class="object centerthis">Something Centered</span> <p>Aeroplanigera Mi Psychopathologia Subdistinctio Chirographum Intuor Sons Superbiloquentia Os Sors Sesquiseptimus Municipatio Archipresbyteratus O Conclusio Compedagogius.</p> </div>

你可以使用位置:相对;然后设置左边和上面的值:

.cenverDiv{
    position:relative;
    left:30%;
    top:0px;
}

.center {
   margin-left: auto;
   margin-right: auto;
}

最小宽度不是全局支持的，但是可以使用

.divclass {
   min-width: 200px;
}

然后可以将div设置为

<div class="center divclass">stuff in here</div>

对这个问题最好的回答是使用margin-auto，但要使用它，你必须知道你的div的宽度在px或%。

CSS代码:

div{
    width:30%;
    margin-left:auto;
    margin-right:auto;
}