使CSS3家族树IE8兼容

Question

我想使用this great CSS3 family tree，但我需要支持IE8。主要问题似乎是:before和:after元素在不应该隐藏的时候，如下图所示。 （第一个大孩子不应该向左边行，最后一个不应该向右行。）

我已经尝试了jQuery后备，但无济于事。这是一个JSFiddle，代码如下。

＆＃13;

＆＃13;

// Add classes for old IE
jQuery(".tree li a:only-child, .tree li:only-child").addClass("only-child");

＆＃13;

/*Now the CSS*/
 * {
    margin: 0;
    padding: 0;
}
.tree ul {
    padding-top: 20px;
    position: relative;
    transition: all 0.5s;
    -webkit-transition: all 0.5s;
    -moz-transition: all 0.5s;
}
.tree li {
    float: left;
    text-align: center;
    list-style-type: none;
    position: relative;
    padding: 20px 5px 0 5px;
    transition: all 0.5s;
    -webkit-transition: all 0.5s;
    -moz-transition: all 0.5s;
}
/*We will use ::before and ::after to draw the connectors*/
 .tree li:before, .tree li:after {
    content:'';
    position: absolute;
    top: 0;
    right: 50%;
    border-top: 1px solid #ccc;
    width: 50%;
    height: 20px;
}
.tree li:after {
    right: auto;
    left: 50%;
    border-left: 1px solid #ccc;
}
/*We need to remove left-right connectors from elements without 
any siblings*/
 .tree li.only-child:after, .tree li.only-child:before {
    display: none;
}
/*Remove space from the top of single children*/
 .tree li.only-child {
    padding-top: 0;
}
/*Remove left connector from first child and 
right connector from last child*/
 .tree li:first-child:before, .tree li:last-child:after {
    border: 0 none;
}
/*Adding back the vertical connector to the last nodes*/
 .tree li:last-child:before {
    border-right: 1px solid #ccc;
    border-radius: 0 5px 0 0;
    -webkit-border-radius: 0 5px 0 0;
    -moz-border-radius: 0 5px 0 0;
}
.tree li:first-child:after {
    border-radius: 5px 0 0 0;
    -webkit-border-radius: 5px 0 0 0;
    -moz-border-radius: 5px 0 0 0;
}
/*Time to add downward connectors from parents*/
 .tree ul ul:before {
    content:'';
    position: absolute;
    top: 0;
    left: 50%;
    border-left: 1px solid #ccc;
    width: 0;
    height: 20px;
}
.tree li a {
    border: 1px solid #ccc;
    padding: 5px 10px;
    text-decoration: none;
    color: #666;
    font-family: arial, verdana, tahoma;
    font-size: 11px;
    display: inline-block;
    border-radius: 5px;
    -webkit-border-radius: 5px;
    -moz-border-radius: 5px;
    transition: all 0.5s;
    -webkit-transition: all 0.5s;
    -moz-transition: all 0.5s;
}


/*Time for some hover effects*/

/*We will apply the hover effect the the lineage of the element also*/
 .tree li a:hover, .tree li a:hover+ul li a {
    background: #c8e4f8;
    color: #000;
    border: 1px solid #94a0b4;
}
/*Connector styles on hover*/
 .tree li a:hover+ul li::after, .tree li a:hover+ul li::before, .tree li a:hover+ul::before, .tree li a:hover+ul ul::before {
    border-color: #94a0b4;
}

＆＃13;

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>

<!-- Borrowed from http://thecodeplayer.com/walkthrough/css3-family-tree -->
<div class="tree">
    <ul>
        <li>	<a href="#">Parent</a>

            <ul>
                <li>	<a href="#">Child</a>

                    <ul>
                        <li>	<a href="#">Grand Child</a>

                        </li>
                    </ul>
                </li>
                <li>	<a href="#">Child</a>

                    <ul>
                        <li><a href="#">Grand Child</a>
                        </li>
                        <li>	<a href="#">Grand Child</a>

                            <ul>
                                <li>	<a href="#">Great Grand Child</a>

                                </li>
                                <li>	<a href="#">Great Grand Child</a>

                                </li>
                                <li>	<a href="#">Great Grand Child</a>

                                </li>
                            </ul>
                        </li>
                        <li><a href="#">Grand Child</a>
                        </li>
                    </ul>
                </li>
            </ul>
        </li>
    </ul>
</div>

＆＃13;

＆＃13;

＆＃13;

Answer 1

导致额外边框的问题是，与:first-child不同，:last-child伪类在IE8及以下版本中不可用。此无法识别的选择器的存在使整个规则无效，导致IE删除以下规则。

/*Remove left connector from first child and 
right connector from last child*/
.tree li:first-child:before, .tree li:last-child:after {
    border: 0 none;
}
/*Adding back the vertical connector to the last nodes*/
.tree li:last-child:before {
    border-right: 1px solid #ccc;
    border-radius: 0 5px 0 0;
    -webkit-border-radius: 0 5px 0 0;
    -moz-border-radius: 0 5px 0 0;
}

要解决此问题，您可以对这些元素使用相同的jQuery addClass策略。

<强> JavaScript的：

jQuery(".tree li:last-child").addClass("last-child");

<强> CSS：

/*Remove left connector from first child and 
right connector from last child*/
.tree li:first-child:before, .tree li.last-child:after {
    border: 0 none;
}
/*Adding back the vertical connector to the last nodes*/
.tree li.last-child:before {
    border-right: 1px solid #ccc;
    border-radius: 0 5px 0 0;
    -webkit-border-radius: 0 5px 0 0;
    -moz-border-radius: 0 5px 0 0;
}

IE8中的屏幕截图：

工作示例（JSFiddle）：

＆＃13;

＆＃13;

$(window).load(function(){
// Add classes for old IE
	jQuery(".tree li a:only-child, .tree li:only-child").addClass("only-child");
	jQuery(".tree li:last-child").addClass("last-child");

});

＆＃13;

/*Now the CSS*/
 * {
    margin: 0;
    padding: 0;
}
.tree ul {
    padding-top: 20px;
    position: relative;
    transition: all 0.5s;
    -webkit-transition: all 0.5s;
    -moz-transition: all 0.5s;
}
.tree li {
    float: left;
    text-align: center;
    list-style-type: none;
    position: relative;
    padding: 20px 5px 0 5px;
    transition: all 0.5s;
    -webkit-transition: all 0.5s;
    -moz-transition: all 0.5s;
}
/*We will use ::before and ::after to draw the connectors*/
 .tree li:before, .tree li:after {
    content:'';
    position: absolute;
    top: 0;
    right: 50%;
    border-top: 1px solid #ccc;
    width: 50%;
    height: 20px;
}
.tree li:after {
    right: auto;
    left: 50%;
    border-left: 1px solid #ccc;
}
/*We need to remove left-right connectors from elements without 
any siblings*/
 .tree li.only-child:after, .tree li.only-child:before {
    display: none;
}
/*Remove space from the top of single children*/
 .tree li.only-child {
    padding-top: 0;
}
/*Remove left connector from first child and 
right connector from last child*/
.tree li:first-child:before, .tree li.last-child:after {
    border: 0 none;
}
/*Adding back the vertical connector to the last nodes*/
 .tree li.last-child:before {
    border-right: 1px solid #ccc;
    border-radius: 0 5px 0 0;
    -webkit-border-radius: 0 5px 0 0;
    -moz-border-radius: 0 5px 0 0;
}
.tree li:first-child:after {
    border-radius: 5px 0 0 0;
    -webkit-border-radius: 5px 0 0 0;
    -moz-border-radius: 5px 0 0 0;
}
/*Time to add downward connectors from parents*/
 .tree ul ul:before {
    content:'';
    position: absolute;
    top: 0;
    left: 50%;
    border-left: 1px solid #ccc;
    width: 0;
    height: 20px;
}
.tree li a {
    border: 1px solid #ccc;
    padding: 5px 10px;
    text-decoration: none;
    color: #666;
    font-family: arial, verdana, tahoma;
    font-size: 11px;
    display: inline-block;
    border-radius: 5px;
    -webkit-border-radius: 5px;
    -moz-border-radius: 5px;
    transition: all 0.5s;
    -webkit-transition: all 0.5s;
    -moz-transition: all 0.5s;
}


/*Time for some hover effects*/

/*We will apply the hover effect the the lineage of the element also*/
 .tree li a:hover, .tree li a:hover+ul li a {
    background: #c8e4f8;
    color: #000;
    border: 1px solid #94a0b4;
}
/*Connector styles on hover*/
 .tree li a:hover+ul li::after, .tree li a:hover+ul li::before, .tree li a:hover+ul::before, .tree li a:hover+ul ul::before {
    border-color: #94a0b4;
}

＆＃13;

<script type="text/javascript" src="//code.jquery.com/jquery-1.11.0.js"></script>


<!-- Borrowed from http://thecodeplayer.com/walkthrough/css3-family-tree -->
<div class="tree">
    <ul>
        <li class="only-child">	<a href="#">Parent</a>

            <ul>
                <li>	<a href="#">Child</a>

                    <ul>
                        <li class="only-child">	<a class="only-child" href="#">Grand Child</a>

                        </li>
                    </ul>
                </li>
                <li>	<a href="#">Child</a>

                    <ul>
                        <li><a class="only-child" href="#">Grand Child</a>
                        </li>
                        <li>	<a href="#">Grand Child</a>

                            <ul>
                                <li>	<a class="only-child" href="#">Great Grand Child</a>

                                </li>
                                <li>	<a class="only-child" href="#">Great Grand Child</a>

                                </li>
                                <li>	<a class="only-child" href="#">Great Grand Child</a>

                                </li>
                            </ul>
                        </li>
                        <li><a class="only-child" href="#">Grand Child</a>
                        </li>
                    </ul>
                </li>
            </ul>
        </li>
    </ul>
</div>

＆＃13;

＆＃13;

＆＃13;