JS实现圆角效果

该插件能实现各种效果的圆角。
需要的JS文件jquery.corner.js代码如下：

jQuery.fn.corner = function(o) {
    function hex2(s) {
        var s = parseInt(s).toString(16);
        return ( s.length < 2 ) ? '0'+s : s;
    };
    function gpc(node) {
        for ( ; node && node.nodeName.toLowerCase() != 'html'; node = node.parentNode  ) {
            var v = jQuery.css(node,'backgroundColor');
            if ( v.indexOf('rgb') >= 0 ) { 
                rgb = v.match(/\d+/g); 
                return '#'+ hex2(rgb[0]) + hex2(rgb[1]) + hex2(rgb[2]);
            }
            if ( v && v != 'transparent' )
                return v;
        }
        return '#ffffff';
    };
    function getW(i) {
        switch(fx) {
        case 'round':  return Math.round(width*(1-Math.cos(Math.asin(i/width))));
        case 'cool':   return Math.round(width*(1+Math.cos(Math.asin(i/width))));
        case 'sharp':  return Math.round(width*(1-Math.cos(Math.acos(i/width))));
        case 'bite':   return Math.round(width*(Math.cos(Math.asin((width-i-1)/width))));
        case 'slide':  return Math.round(width*(Math.atan2(i,width/i)));
        case 'jut':    return Math.round(width*(Math.atan2(width,(width-i-1))));
        case 'curl':   return Math.round(width*(Math.atan(i)));
        case 'tear':   return Math.round(width*(Math.cos(i)));
        case 'wicked': return Math.round(width*(Math.tan(i)));
        case 'long':   return Math.round(width*(Math.sqrt(i)));
        case 'sculpt': return Math.round(width*(Math.log((width-i-1),width)));
        case 'dog':    return (i&1) ? (i+1) : width;
        case 'dog2':   return (i&2) ? (i+1) : width;
        case 'dog3':   return (i&3) ? (i+1) : width;
        case 'fray':   return (i%2)*width;
        case 'notch':  return width; 
        case 'bevel':  return i+1;
        }
    };
    o = (o||"").toLowerCase();
    var keep = /keep/.test(o);                       // keep borders?
    var cc = ((o.match(/cc:(#[0-9a-f]+)/)||[])[1]);  // corner color
    var sc = ((o.match(/sc:(#[0-9a-f]+)/)||[])[1]);  // strip color
    var width = parseInt((o.match(/(\d+)px/)||[])[1]) || 10; // corner width
    var re = /round|bevel|notch|bite|cool|sharp|slide|jut|curl|tear|fray|wicked|sculpt|long|dog3|dog2|dog/;
    var fx = ((o.match(re)||['round'])[0]);
    var edges = { T:0, B:1 };
    var opts = {
        TL:  /top|tl/.test(o),       TR:  /top|tr/.test(o),
        BL:  /bottom|bl/.test(o),    BR:  /bottom|br/.test(o)
    };
    if ( !opts.TL && !opts.TR && !opts.BL && !opts.BR )
        opts = { TL:1, TR:1, BL:1, BR:1 };
    var strip = document.createElement('div');
    strip.style.overflow = 'hidden';
    strip.style.height = '1px';
    strip.style.backgroundColor = sc || 'transparent';
    strip.style.borderStyle = 'solid';
    return this.each(function(index){
        var pad = {
            T: parseInt(jQuery.css(this,'paddingTop'))||0,     R: parseInt(jQuery.css(this,'paddingRight'))||0,
            B: parseInt(jQuery.css(this,'paddingBottom'))||0,  L: parseInt(jQuery.css(this,'paddingLeft'))||0
        };

        if (jQuery.browser.msie) this.style.zoom = 1; // force 'hasLayout' in IE
        if (!keep) this.style.border = 'none';
        strip.style.borderColor = cc || gpc(this.parentNode);
        var cssHeight = jQuery.curCSS(this, 'height');

        for (var j in edges) {
            var bot = edges[j];
            strip.style.borderStyle = 'none '+(opts[j+'R']?'solid':'none')+' none '+(opts[j+'L']?'solid':'none');
            var d = document.createElement('div');
            var ds = d.style;

            bot ? this.appendChild(d) : this.insertBefore(d, this.firstChild);

            if (bot && cssHeight != 'auto') {
                if (jQuery.css(this,'position') == 'static')
                    this.style.position = 'relative';
                ds.position = 'absolute';
                ds.bottom = ds.left = ds.padding = ds.margin = '0';
                if (jQuery.browser.msie)
                    ds.setExpression('width', 'this.parentNode.offsetWidth');
                else
                    ds.width = '100%';
            }
            else {
                ds.margin = !bot ? '-'+pad.T+'px -'+pad.R+'px '+(pad.T-width)+'px -'+pad.L+'px' : 
                                    (pad.B-width)+'px -'+pad.R+'px -'+pad.B+'px -'+pad.L+'px';                
            }

            for (var i=0; i < width; i++) {
                var w = Math.max(0,getW(i));
                var e = strip.cloneNode(false);
                e.style.borderWidth = '0 '+(opts[j+'R']?w:0)+'px 0 '+(opts[j+'L']?w:0)+'px';
                bot ? d.appendChild(e) : d.insertBefore(e, d.firstChild);
            }
        }
    });
};

测试用的HTML文件：

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<!-- saved from url=(0014)about:internet -->
<head>
<meta http-equiv="content-type" content="text/html; charset=UTF-8" />
<meta http-equiv="Content-Style-Type" content="text/css" />
<title>JQuery Corner Demo by http://www.codefans.net</title>
<style type="text/css">
body {
    font: Verdana,Arial,sans-serif;
	 /* An explicit background color is required for Safari. */
	 /* Otherwise your corner chunks will come out black!    */
	background: #f8f0e0;
}
div.section { clear: left; }
h1 { font-size: 150%; padding: 0 }
h2 { background: #ccc; padding: 1px 20px;  }
div.demo { 
	float: left; width: 18em; padding: 20px; margin: 1em;
    background: #c92; color:#000; text-align: center; font: verdana, arial, sans-serif;
}
div.fun  { margin: 2px; }
</style>

<script type="text/javascript" src="jquery.js"></script>
<script type="text/javascript" src="jquery.corner.js"></script>
<script type="text/javascript">
	$(function(){	// shorthand for $(document).ready() BTW
        $('div.demo').each(function() {
			// The text of the paragraphs in the rounded divs is also the
			// jQuery code needed to create that effect. Cosmic.
             eval($('p', this).text());
        });
        $('#main p').wrap("<code></code>");
	});
</script>
</head>
<body>
<h1>jQuery Corner Demo download by http://www.codefans.net(OLD)</h1>

<p><b>
For the most recent version of this plugin, go to
<a href="http://www.malsup.com/jquery/corner/">http://www.malsup.com/jquery/corner/</a>
</b></p>

<p>Now with more effects, thanks to <a href="http://www.malsup.com/jquery/corner/">Mike Alsup</a>!</p>
<p><a href="jq-corner.html">How does this work? How do I use it?</a></p>
<p><a href="jquery.corner.js">Just the source, please!</a></p>

<div id="main">
    <div class="section">
    <h1>Available Corner Effects</h1>
    </div>
    <div class="demo"><h1>Round</h1> <p>$(this).corner();</p></div>
    <div class="demo"><h1>Bevel</h1> <p>$(this).corner("bevel");</p></div>
    <div class="demo"><h1>Notch</h1> <p>$(this).corner("notch");</p></div>
    <div class="demo"><h1>Bite</h1>  <p>$(this).corner("bite");</p></div>
    <div class="demo"><h1>Cool</h1>  <p>$(this).corner("cool");</p></div>
    <div class="demo"><h1>Sharp</h1> <p>$(this).corner("sharp");</p></div>
    <div class="demo"><h1>Slide</h1> <p>$(this).corner("slide");</p></div>
    <div class="demo"><h1>Jut</h1>   <p>$(this).corner("jut");</p></div>
    <div class="demo"><h1>Curl</h1>  <p>$(this).corner("curl");</p></div>
    <div class="demo"><h1>Tear</h1>  <p>$(this).corner("tear");</p></div>
    <div class="demo"><h1>Fray</h1>  <p>$(this).corner("fray");</p></div>
    <div class="demo"><h1>Wicked</h1><p>$(this).corner("wicked");</p></div>
    <div class="demo"><h1>Sculpt</h1><p>$(this).corner("sculpt");</p></div>
    <div class="demo"><h1>Long</h1>  <p>$(this).corner("long");</p></div>
    <div class="demo"><h1>Dog Ear</h1><p>$(this).corner("dog");</p></div>
    <div class="demo"><h1>Dog2</h1><p>$(this).corner("dog2");</p></div>
    <div class="demo"><h1>Dog3</h1><p>$(this).corner("dog3");</p></div>
    
    
    <div class="section">
    <h1>Choose Your Corner</h1>
    <h2>Use <code>top, bottom, tl, tr, bl, br</code> to identify which corner to style</h2>
    </div>
    <div class="demo"><h1>Top Bevel</h1>        <p>$(this).corner("bevel top");</p></div>
    <div class="demo"><h1>Top-Left Bite</h1>    <p>$(this).corner("bite tl");</p></div>
    <div class="demo"><h1>Round Bottom</h1>     <p>$(this).corner("bottom");</p></div>
    <div class="demo"><h1>Bottom-Left Notch</h1><p>$(this).corner("notch bl");</p></div>
    <div class="demo"><h1>Top-Right Dog Ear</h1><p>$(this).corner("dog tr");</p></div>
    <div class="demo"><h1>Top-Left, Bottom-Right Cool</h1><p>$(this).corner("cool tl br");</p></div>
    
    <div class="section">
    <h1>Specify Size</h1>
    <h2>Include a px value to specify the corner size</h2>
    </div>
    <div class="demo"><h1>Round 30px</h1> <p>$(this).corner("30px");</p></div>
    <div class="demo"><h1>Round 5px</h1>  <p>$(this).corner("5px");</p></div>
    <div class="demo"><h1>Cool 20px</h1>  <p>$(this).corner("cool 20px");</p></div>
    <div class="demo"><h1>Sharp 20px</h1> <p>$(this).corner("sharp 20px");</p></div>
    <div class="demo"><h1>Bite 30px</h1>  <p>$(this).corner("bite 30px");</p></div>
    <div class="demo"><h1>Wicked 20px</h1><p>$(this).corner("wicked 20px");</p></div>
    <div class="demo"><h1>Dog 20px</h1><p>$(this).corner("dog 20px");</p></div>
    <div class="demo"><h1>Dog2 30px</h1><p>$(this).corner("dog2 30px");</p></div>
    <div class="demo"><h1>Dog3 30px</h1><p>$(this).corner("dog3 30px");</p></div>
    
    <div class="section">
    <h1>Mix and Match</h1>
    <h2>Chain corner calls to achieve combined effects</h2>
    </div>
    <div class="demo"><h1>Round and Bevel</h1><p>$(this).corner( "bottom").corner("top bevel");</p></div>
    <div class="demo"><h1>Round and Notch</h1><p>$(this).corner( "br top").corner("notch bl 20px");</p></div>
    <div class="demo"><h1>Crazy</h1>          <p>$(this).corner("jut tl 20px").corner("dog tr 20px").corner("bite bl 15px").corner("notch br");</p></div>

    <div class="section">
    <h1>Fun Stuff</h1>
    <h2>Interesting Side Effects</h2>
    </div>
    <div class="demo fun"><h1>Left Half of Arrow</h1> <p>$(this).corner("sharp tr br 20px");</p></div>
    <div class="demo fun"><h1>Right Half of Arrow</h1><p>$(this).corner("sharp tl bl 20px");</p></div>
</div> <!-- main -->
</body>
</html>