font

概述

font 属性是设置 font-style, font-variant, font-weight, font-size, line-height 和 font-family属性的简写，或使用特定的关键字设置元素的字体为某个系统字体。

和其它的CSS简写属性一样，该属性中未被设置的属性值使用它们各自的初始值，并覆盖之前由非简写的属性设置的值。

语法

/* size | family */
font: 2em "Open Sans", sans-serif;

/* style | size | family */
font: italic 2em "Open Sans", sans-serif;

/* style | variant | weight | size/line-height | family */
font: italic small-caps bolder 16px/3 cursive;

/* The font used in system dialogs */
font: message-box;

值

<'font-style'>

见 font-style 属性。

<'font-variant'>

见 font-variant 属性。

<'font-weight'>

见 font-weight 属性。

<'font-size'>

见 font-size 属性。

<'line-height'>

见 line-height 属性。

<'font-family'>

见 font-family 属性。

caption icon menu message-box small-caption status-bar

关键字用于表示某个特定的系统字体，以代替每个单独的普通属性：

caption	用于标题控件（如按钮，下拉列表等）的字体。
icon	用于标签图标的字体。
menu	菜单中（如下拉菜单和菜单列表）使用的字体。
message-box	用于对话框的字体。
small-caption	用于小标号控件的字体。
status-bar	用于窗口状态栏的字体。

实现这些关键字的浏览器经常会多实现几个带前缀的关键字； Gecko 实现了 -moz-window, -moz-document, -moz-desktop, -moz-info, -moz-dialog, -moz-button, -moz-pull-down-menu, -moz-list 和 -moz-field.

正式语法

[ [ <‘font-style’> || <font-variant-css21> || <‘font-weight’> || <‘font-stretch’> ]? <‘font-size’> [ / <‘line-height’> ]? <‘font-family’> ] | caption | icon | menu | message-box | small-caption | status-bar
where 
<font-variant-css21> = [normal | small-caps]

示例

/* Set the font size to 12px and the line height to 14px. Set the font family to sans-serif */
p { font: 12px/14px sans-serif }

/* Set the font size to 80% of the parent element or default value (if no parent element present) 
and set the font family to sans-serif */ 
p { font: 80% sans-serif }

/* Set the font weight to bold, the font-style to italic, the font size to large, 
and the font family to serif. */
p { font: bold italic large serif }

/* Use the same font as the status bar of the window */
p { font: status-bar }

实样

HTML Content

<p>
    Change the radio buttons below to see the generated shorthand and it's effect.
</p>
<form action="createShortHand()">
    <div class="cf">
        <div class="setPropCont">
            font-style<br/>
            <input type="radio" id="font-style-none" name="font_style" checked="" value="" onchange="setCss()"> <label for="font-style-none">none</label><br/>
            <input type="radio" id="font-style-normal" name="font_style" value="normal" onchange="setCss()"> <label for="font-style-normal">normal</label><br/>
            <input type="radio" id="font-style-italic" name="font_style" value="italic" onchange="setCss()"> <label for="font-style-italic">italic</label><br/>
            <input type="radio" id="font-style-oblique" name="font_style" value="oblique" onchange="setCss()"> <label for="font-style-oblique">oblique</label>
        </div>
        
        <div class="setPropCont">
            font-variant<br>
            <input type="radio" id="font-variant-none" name="font_variant" checked="" value=" " onchange="setCss()"> <label for="font-variant-none">none</label><br/>
            <input type="radio" id="font-variant-normal" name="font_variant" value="normal" onchange="setCss()"> <label for="font-variant-normal">normal</label><br/>
            <input type="radio" id="font-variant-small-caps" name="font_variant" value="small-caps" onchange="setCss()"> <label for="font-variant-small-caps">small-caps</label>
        </div>
        
        <div class="setPropCont">
            font-weight<br/>
            <input type="radio" id="font-weight-none" name="font_weight" value="" onchange="setCss()"> <label for="font-weight-none">none</label><br/>
            <input type="radio" id="font-weight-normal" checked="" name="font_weight" value="400" onchange="setCss()"> <label for="font-weight-normal">normal</label><br/>
            <input type="radio" id="font-weight-bold" name="font_weight" value="700" onchange="setCss()"> <label for="font-weight-bold">bold</label>
        </div>
        
        <div class="setPropCont">
            font-size<br/>
            <input type="radio" id="font-size-12px" name="font_size" value="12px" onchange="setCss()"> <label for="font-size-12px">12px</label><br/>
            <input type="radio" id="font-size-16px" name="font_size" value="16px" checked="" onchange="setCss()"> <label for="font-size-16px">16px</label><br/>
            <input type="radio" id="font-size-24px" name="font_size" value="24px" onchange="setCss()"> <label for="font-size-24px">24px</label>
        </div>
        
        <div class="setPropCont">
            line-height<br/>
            <input type="radio" id="line-height-none" name="line_height" checked="" value="" onchange="setCss()"> <label for="line-height-none">none</label><br/>
            <input type="radio" id="line-height-1.2" name="line_height" value="/1.2" onchange="setCss()"> <label for="line-height-1.2">1.2</label><br/>
            <input type="radio" id="line-height-3" name="line_height" value="/3" onchange="setCss()"> <label for="line-height-3">3</label>
        </div>
        
        <div class="setPropCont">
            font-family<br/>
            <input type="radio" id="font-family-courier" name="font_family" checked="" value="courier" onchange="setCss(5,'courier')"> <label for="font-family-courier">courier</label><br/>
            <input type="radio" id="font-family-serif" name="font_family" value="serif" onchange="setCss()"> <label for="font-family-serif">serif</label><br/>
            <input type="radio" id="font-family-sans-serif" name="font_family" value="sans-serif" onchange="setCss()"> <label for="font-family-sans-serif">sans-serif</label>
        </div>
    </div>

    <div class="cf propInputs">
        <div class="propInputCont tar">
            font :
        </div>
        <div class="propInputCont">
            <input type="text" class="curCss" id="input_font_style"><br/>
            font-style <br/>
            optional
        
        </div>
        <div class="propInputCont">
            <input type="text" class="curCss" id="input_font_variant"> <br/>
            font-variant <br/>
            optional
        </div>
        <div class="propInputCont">
            <input type="text" class="curCss" id="input_font_weight"> <br/>
            font-weight <br/>
            optional
        </div>
        <div class="propInputCont">
            <input type="text" class="curCss mandatory" id="input_font_size"> <br/>
            font-size <br/>
            mandatory
        </div>
        <div class="propInputCont">
            <input type="text" class="curCss" id="input_line_height"> <br/>
            line-height <br/>
            optional
        </div>
        <div class="propInputCont">
            <input type="text" class="curCss mandatory" id="input_font_family"> <br/>
            font-family <br/>
            mandatory
        </div>
    </div>
</form>

<div class="fontShortHand">
    This is some sample text.
</div>

CSS Content

body, input {
  font: 14px arial;
}

.propInputCont {
  float: left;
  text-align: center;
  margin-right: 5px;
  width: 80px;
}

.setPropCont {
  float: left;
  margin-right: 5px;
  width: 120px;
}

.propInputs, .setPropCont {
  margin-bottom: 1em;
}

.curCss {
  border: none;
  border-bottom: 1px solid black;
  text-align: center;
  width: 80px;
}

.mandatory {
  border-bottom-color: red;
}

.cf:before,
.cf:after {
  content: " ";
  display: table;
}

.cf:after {
  clear: both;
}

.tar {
  width: 40px;
  text-align: right;
}

JavaScript Content

var textAreas = document.getElementsByClassName("curCss"),
    shortText = "",
    getCheckedValue,
    setCss,
    getProperties,
    injectCss;

getProperties = function () {
  shortText =
      getCheckedValue("font_style") + " " +
      getCheckedValue("font_variant") + " " +
      getCheckedValue("font_weight") + " " +
      getCheckedValue("font_size") +
      getCheckedValue("line_height") + " " +
      getCheckedValue("font_family");

  return shortText;
}

getCheckedValue = function(radio_name) {
  oRadio = document.forms[0].elements[radio_name];
  for (var i = 0; i < oRadio.length; i++) {
    if(oRadio[i].checked) {
      var propInput = "input_" + radio_name,
          curElemName = "input_" + radio_name,
          curElem = document.getElementById(curElemName);
      curElem.value = oRadio[i].value;

      return oRadio[i].value;
    }
  }
}

setCss = function () {
  getProperties();
  injectCss(shortText);
}

injectCss = function(cssFragment) {
  old = document.body.getElementsByTagName("style");
  if (old.length > 1) {
    old[1].parentElement.removeChild(old[1]);
  }
  css = document.createElement("style");
  css.innerHTML = ".fontShortHand{font: " + cssFragment + "}";
  document.body.appendChild(css);
}

setCss();

规范

浏览器兼容性