如何将 < ul > < li > 中心化为一个 div？

Try

div#divID ul {margin:0 auto;}

Since ul and li elements are display: block by default — give them auto margins and a width that is smaller than their container.

ul {
width: 70%;
margin: auto;
}

If you've changed their display property, or done something that overrides normal alignment rules (such as floating them) then this won't work.

To center a block object (e.g. the ul) you need to set a width on it and then you can set that objects left and right margins to auto.

To center the inline content of block object (e.g. the inline content of li) you can set the css property text-align: center;.

Could either be

div ul
{
width: [INSERT FIXED WIDTH]
margin: 0 auto;
}

or

div li
{
text-align: center;
}

depends on how it should look like (or combining those)

use oldschool center-tags

<div> <center> <ul> <li>...</li> </ul></center> </div>

:-)

If you know the width of the ul then you can simply set the margin of the ul to 0 auto;

This will align the ul in the middle of the containing div

Example:

HTML:

<div id="container">
<ul>
<li>Item1</li>
<li>Item2</li>
</ul>
<div>

CSS:

  #container ul{
width:300px;
margin:0 auto;
}

Just add text-align: center; to your <ul>. Problem solved.

<div id="container">
<table width="100%" height="100%">
<tr>
<td align="center" valign="middle">
<ul>
<li>item 1</li>
<li>item 2</li>
<li>item 3</li>
</ul>
</td>
</tr>
</table>
</div>

To center the ul and also have the li elements centered in it as well, and make the width of the ul change dynamically, use display: inline-block; and wrap it in a centered div.

<style type="text/css">
.wrapper {
text-align: center;
}
.wrapper ul {
display: inline-block;
margin: 0;
padding: 0;
/* For IE, the outcast */
zoom:1;
*display: inline;
}
.wrapper li {
float: left;
padding: 2px 5px;
border: 1px solid black;
}
</style>


<div class="wrapper">
<ul>
<li>Three</li>
<li>Blind</li>
<li>Mice</li>
</ul>
</div>

Update

Here is a jsFiddle link to the code above.

Interesting but try this with floated li elements inside the ul: Example here

The problem now: the ul needs a fixed width to actually sit in the center. However we want to be it relative to the container width (or dynamic), margin: 0 auto on the ul does not work.

A better way is to let go of UL/Li list and use a different approach example here

Steps :

1. Write style="text-align:center;" to parent div of ul
2. Write style="display:inline-table;" to ul
3. Write style="display:inline;" to li

or use

<div class="menu">
<ul>
<li>item 1 </li>
<li>item 2 </li>
<li>item 3 </li>
</ul>
</div>


<style>
.menu { text-align: center; }
.menu ul { display:inline-table; }
.menu li { display:inline; }
</style>

Here is the solution I could find:

#wrapper {
float:right;
position:relative;
left:-50%;
text-align:left;
}
#wrapper ul {
list-style:none;
position:relative;
left:50%;
}


#wrapper li{
float:left;
position:relative;
}

Another option is:

HTML

<nav>
<ul class = "main-nav">
<li> Productos </li>
<li> Catalogo </li>
<li> Contact </li>
<li> Us </li>
</ul>
</nav>

CSS:

nav {
text-align: center;
}


nav .main-nav li {
float: left;
width: 20%;
margin-right: 5%;
font-size: 36px;
text-align: center;
}

This is a better way to center UL's inside of any DIV container.

This CSS solution does not use Width and Float properties. Float:Left and Width: 70%, will cause you headaches when you need to duplicate your menu on different pages with different menu items.

Instead of using width, we use padding and margin to determine the space around the text/menu item. Also, instead of using Float:Left in the LI element, use display:inline-block.

By floating your LI left, you literally float your content to the left and then you must use one of the Hacks mentioned above to center your UL. Display:inline-block creates your Float property for you (sort of). It takes your LI element and turns it into a block element that lays side by side each other (not floating).

With Responsive design and using frameworks like Bootstrap or Foundation, there will be issues when trying to float and center content. They have some built-in classes, but it's always better to do it from scratch. This solution is much better for dynamic menus (Such as Adobe Business Catalyst menu system).

Reference for this tutorial can be found at: http://html-tuts.com/center-div-image-table-ul-inside-div/

HTML

<div class="container">
<ul>
<li><a href="#">Button</a></li>
<li><a href="#">Button</a></li>
<li><a href="#">Button</a></li>
<li><a href="#">Button</a></li>
<li><a href="#">Button</a></li>
</ul>
</div>

CSS

.container {
text-align: center;
border: 1px solid green;
}
.container ul {
border: 2px solid red;
display: inline-block;
margin: 10px 0;
padding: 2px;
}
.container li {
display: inline-block;
}
.container li a {
display: inline-block;
background: #444;
color: #FFF;
padding: 5px;
text-decoration: none;
}

I have been looking for the same case and tried all answers by change the width of <li>.
Unfortunately all were failed to get the same distance on left and right of the <ul> box.

The closest match is this answer but it needs to adjust the change of width with padding

.container ul {
...
padding: 10px 25px;
}


.container li {
...
width: 100px;
}

See the result below, all distance between <li> also to the <ul> box are the same.

You may check it on this jsFiddle:
http://jsfiddle.net/qwbexxog/14/

I love flexbox:

ul {
justify-content: center;
display: flex;
}