工具提示定位纯css

div { position: absolute; top: 50%; left: 50%; transform: translate(-50%, -50%); -ms-transform: translate(-50%, -50%); /* IE 9 */ -webkit-transform: translate(-50%, -50%); /* Chrome, Safari, Opera */ text-align: center; } .tooltip { position: relative; display: inline-block; border-bottom: 1px dotted black; } .tooltip .tooltiptext { visibility: hidden; width: 120px; background-color: black; color: #fff; //text-align: center; border-radius: 6px; padding: 5px 0; /* Position the tooltip */ position: absolute; z-index: 1; } .tooltip:hover .tooltiptext { visibility: visible; } .toolLeft { top: -5px; right: 105%; } .toolRight { top: -5px; left: 105%; } .toolTop { bottom: 100%; left: 50%; margin-left: -60px; } .toolBottom { top: 100%; left: 50%; margin-left: -60px; } <div> <div class="tooltip">Top <span class="tooltiptext toolTop">Tooltip text</span></div><br /> <div class="tooltip">Left <span class="tooltiptext toolLeft">Tooltip text</span></div><br /> <div class="tooltip">Right <span class="tooltiptext toolRight">Tooltip text</span></div><br /> <div class="tooltip">Bottom <span class="tooltiptext toolBottom">Tooltip text</span></div><br /> </div>

我做了一些事情，应该能够适应一个div以及。

HTML

<td>
    <%# (Eval("Name").ToString().Length > 65) ? Eval("Name").ToString().Substring(0, 60) + "..." : Eval("Name")%>
    <span class="showonhover">
        <a href="#"><%# (Eval("Name").ToString().Length > 65) ? "More" : "" %></a>
        <span class="hovertext">
            <%# Eval("Name") %>
        </span>
    </span>
</td>

CSS

.showonhover .hovertext { display: none;}
.showonhover:hover .hovertext {display: inline;}
a.viewdescription {color:#999;}
a.viewdescription:hover {background-color:#999; color: White;}
.hovertext {position:absolute;z-index:1000;border:1px solid #ffd971;background-color:#fffdce;padding:11px;width:150px;font-size: 0.75em;}

要了解更深入的讨论，请参阅我的文章:

一个简单的格式化工具提示文本悬停

我为它创造了一个公式。 首先是html

<div class="tooltip-container">
  <button class="tooltip-tarjet">
    My Button
  </button>
  <div class="tooltip-element"> 
    This is my tooltip content right here...
  </div>
</div>

现在是它的css

.tooltip-container { 
  /* it contains the tooltip message and the one firing the tooltip
   * it has position relative since it allows for a better responsive positioning
   * of the tooltip-element */
  display: inline-block;
  position: relative;
  flex-direction: row;
}
.tooltip-tarjet:hover + .tooltip-element {
  /* this selector rule matches the tooltip-element right after
   * tooltip-tarjet at a hover action
   *  */
  display: inline-block;
  position: absolute;
  background-color: #869096;
  color: white;
  opacity: 1;
  transition: all 1s;
}
.tooltip-element { 
  /* here goes the tooltip-element styles and positioning, now your
   * tooltip element will always remain to your desired positionno matter
   * the screen size at hand 
   *  */ 
  display: none; 
  opacity: 0;
  text-align: center;
  padding: 7px;
  z-index: 10;
  width: 200px;
  left: -60px;
  bottom: 48px;
  border-radius: 5px;
  -webkit-border-radius: 5px;
  -moz-border-radius: 5px;
  font-size: 12px;
  line-height: 1.5;
}

你可以用简单的css…Jsfiddle这里你可以看到这个例子

下面是工具提示的CSS代码

[data-tooltip] {
  position: relative;
  z-index: 2;
  cursor: pointer;
}

/* Hide the tooltip content by default */
[data-tooltip]:before,
[data-tooltip]:after {
  visibility: hidden;
  -ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=0)";
  filter: progid: DXImageTransform.Microsoft.Alpha(Opacity=0);
  opacity: 0;
  pointer-events: none;
}

/* Position tooltip above the element */
[data-tooltip]:before {
  position: absolute;
  bottom: 150%;
  left: 50%;
  margin-bottom: 5px;
  margin-left: -80px;
  padding: 7px;
  width: 160px;
  -webkit-border-radius: 3px;
  -moz-border-radius: 3px;
  border-radius: 3px;
  background-color: #000;
  background-color: hsla(0, 0%, 20%, 0.9);
  color: #fff;
  content: attr(data-tooltip);
  text-align: center;
  font-size: 14px;
  line-height: 1.2;
}

/* Triangle hack to make tooltip look like a speech bubble */
[data-tooltip]:after {
  position: absolute;
  bottom: 150%;
  left: 50%;
  margin-left: -5px;
  width: 0;
  border-top: 5px solid #000;
  border-top: 5px solid hsla(0, 0%, 20%, 0.9);
  border-right: 5px solid transparent;
  border-left: 5px solid transparent;
  content: " ";
  font-size: 0;
  line-height: 0;
}

/* Show tooltip content on hover */
[data-tooltip]:hover:before,
[data-tooltip]:hover:after {
  visibility: visible;
  -ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=100)";
  filter: progid: DXImageTransform.Microsoft.Alpha(Opacity=100);
  opacity: 1;
}

下面是一个简单的工具提示实现，它可以考虑鼠标的位置以及窗口的高度和宽度:

function showTooltip(e) { var tooltip = e.target.classList.contains("tooltip") ? e.target : e.target.querySelector(":scope .tooltip"); tooltip.style.left = (e.pageX + tooltip.clientWidth + 10 < document.body.clientWidth) ? (e.pageX + 10 + "px") : (document.body.clientWidth + 5 - tooltip.clientWidth + "px"); tooltip.style.top = (e.pageY + tooltip.clientHeight + 10 < document.body.clientHeight) ? (e.pageY + 10 + "px") : (document.body.clientHeight + 5 - tooltip.clientHeight + "px"); } var tooltips = document.querySelectorAll('.couponcode'); for(var i = 0; i < tooltips.length; i++) { tooltips[i].addEventListener('mousemove', showTooltip); } .couponcode { color: red; cursor: pointer; } .couponcode:hover .tooltip { display: block; } .tooltip { position: absolute; white-space: nowrap; display: none; background: #ffffcc; border: 1px solid black; padding: 5px; z-index: 1000; color: black; } Lorem ipsum dolor sit amet, <span class="couponcode">consectetur adipiscing<span class="tooltip">This is a tooltip</span></span> elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in <span class="couponcode">reprehenderit<span class="tooltip">This is another tooltip</span></span> in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est <span class="couponcode">laborum<span class="tooltip">This is yet another tooltip</span></span>.

(也可以参看这把小提琴)

我开发了三种类型的褪色效果:

/* setup tooltips */ .tooltip { position: relative; } .tooltip:before, .tooltip:after { display: block; opacity: 0; pointer-events: none; position: absolute; } .tooltip:after { border-right: 6px solid transparent; border-bottom: 6px solid rgba(0,0,0,.75); border-left: 6px solid transparent; content: ''; height: 0; top: 20px; left: 20px; width: 0; } .tooltip:before { background: rgba(0,0,0,.75); border-radius: 2px; color: #fff; content: attr(data-title); font-size: 14px; padding: 6px 10px; top: 26px; white-space: nowrap; } /* the animations */ /* fade */ .tooltip.fade:after, .tooltip.fade:before { transform: translate3d(0,-10px,0); transition: all .15s ease-in-out; } .tooltip.fade:hover:after, .tooltip.fade:hover:before { opacity: 1; transform: translate3d(0,0,0); } /* expand */ .tooltip.expand:before { transform: scale3d(.2,.2,1); transition: all .2s ease-in-out; } .tooltip.expand:after { transform: translate3d(0,6px,0); transition: all .1s ease-in-out; } .tooltip.expand:hover:before, .tooltip.expand:hover:after { opacity: 1; transform: scale3d(1,1,1); } .tooltip.expand:hover:after { transition: all .2s .1s ease-in-out; } /* swing */ .tooltip.swing:before, .tooltip.swing:after { transform: translate3d(0,30px,0) rotate3d(0,0,1,60deg); transform-origin: 0 0; transition: transform .15s ease-in-out, opacity .2s; } .tooltip.swing:after { transform: translate3d(0,60px,0); transition: transform .15s ease-in-out, opacity .2s; } .tooltip.swing:hover:before, .tooltip.swing:hover:after { opacity: 1; transform: translate3d(0,0,0) rotate3d(1,1,1,0deg); } /* basic styling: has nothing to do with tooltips: */ h1 { padding-left: 50px; } ul { margin-bottom: 40px; } li { cursor: pointer; display: inline-block; padding: 0 10px; } <h1>FADE</h1> <div class="tooltip fade" data-title="Hypertext Markup Language"> <label>Name</label> <input type="text"/> </div> <h1>EXPAND</h1> <div class="tooltip expand" data-title="Hypertext Markup Language"> <label>Name</label> <input type="text"/> </div> <h1>SWING</h1> <div class="tooltip swing" data-title="Hypertext Markup Language"> <label>Name</label> <input type="text"/> </div>