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>

你可以在CSS上使用margin: 0 auto而不是margin-left: auto;margin-right:汽车;

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;
}

如果你的<div>有position: absolute你需要使用width: 100%;

#parent {
    width: 100%;
    text-align: center;
}

    #child {
        display: inline-block;
    }

在你的html文件中，你写:

<div class="banner">
  Center content
</div>

你写的CSS文件:

.banner {
display: block;
margin: auto;
width: 100px;
height: 50px;
}

对我有用。

请使用下面的代码，您的div将在中心。

.class-name {
    display:block;
    margin:0 auto;
}