jQuery 中关于CSS操作部分使用说明

刚刚看了下jQuery的源代码，其中关于CSS及className的操作思想确实很不错，值得借鉴。
其中关于jQuery.className.has的定义部分，是用的正则来实现的，其实此处直接利用Javascript中String对象的indexOf方法来作处理的话，比用正则效率会更些，因此复制代码代码如下:
jQuery.className.has的定义可以改进成：
    has: function( t, c ) {
      t = t.className || t;
      t = " " + t + " ";
      c = " " + c + " ";
      return t.indexOf(c)>-1;
    }

原代码中关于CSS及className的操作部分节选如下：
复制代码代码如下:
  className: {
    // internal only, use addClass("class")
    add: function( elem, c ){
      jQuery.each( c.split(/\s+/), function(i, cur){
        if ( !jQuery.className.has( elem.className, cur ) )
          elem.className += ( elem.className ? " " : "" ) + cur;
      });
    },

    // internal only, use removeClass("class")
    remove: function( elem, c ){
      elem.className = c ?
        jQuery.grep( elem.className.split(/\s+/), function(cur){
          return !jQuery.className.has( c, cur );
        }).join(" ") : "";
    },

    // internal only, use is(".class")
    has: function( t, c ) {
      t = t.className || t;
      // escape regex characters
      c = c.replace(/([\.\\\+\*\?\[\^\]\$\{\}\=\!\<\>\|\:])/g, "\\$1");
      return t && new RegExp("(^|\\s)" + c + "(\\s|$)").test( t );
    }
  },
  swap: function(e,o,f) {
    for ( var i in o ) {
      e.style["old"+i] = e.style[i];
      e.style[i] = o[i];
    }
    f.apply( e, [] );
    for ( var i in o )
      e.style[i] = e.style["old"+i];
  },

  css: function(e,p) {
    if ( p == "height" || p == "width" ) {
      var old = {}, oHeight, oWidth, d = ["Top","Bottom","Right","Left"];

      jQuery.each( d, function(){
        old["padding" + this] = 0;
        old["border" + this + "Width"] = 0;
      });

      jQuery.swap( e, old, function() {
        if (jQuery.css(e,"display") != "none") {
          oHeight = e.offsetHeight;
          oWidth = e.offsetWidth;
        } else {
          e = jQuery(e.cloneNode(true))
            .find(":radio").removeAttr("checked").end()
            .css({
              visibility: "hidden", position: "absolute", display: "block", right: "0", left: "0"
            }).appendTo(e.parentNode)[0];

          var parPos = jQuery.css(e.parentNode,"position");
          if ( parPos == "" || parPos == "static" )
            e.parentNode.style.position = "relative";

oHeight = e.clientHeight;
oWidth = e.clientWidth;

if ( parPos == "" || parPos == "static" )
e.parentNode.style.position = "static";

          e.parentNode.removeChild(e);
        }
      });

return p == "height" ? oHeight : oWidth;
}

return jQuery.curCSS( e, p );
},

curCSS: function(elem, prop, force) {
var ret;

if (prop == "opacity" && jQuery.browser.msie)
return jQuery.attr(elem.style, "opacity");

if (prop == "float" || prop == "cssFloat")
prop = jQuery.browser.msie ? "styleFloat" : "cssFloat";

if (!force && elem.style[prop])
ret = elem.style[prop];

else if (document.defaultView && document.defaultView.getComputedStyle) {

if (prop == "cssFloat" || prop == "styleFloat")
prop = "float";

prop = prop.replace(/([A-Z])/g,"-$1").toLowerCase();
var cur = document.defaultView.getComputedStyle(elem, null);

      if ( cur )
        ret = cur.getPropertyValue(prop);
      else if ( prop == "display" )
        ret = "none";
      else
        jQuery.swap(elem, { display: "block" }, function() {
         var c = document.defaultView.getComputedStyle(this, "");
         ret = c && c.getPropertyValue(prop) || "";
        });

} else if (elem.currentStyle) {

var newProp = prop.replace(/\-(\w)/g,function(m,c){return c.toUpperCase();});
ret = elem.currentStyle[prop] || elem.currentStyle[newProp];

}

return ret;
},

附录：
jQuery官方网站：http://jquery.com/
jQuery源码下载：http://docs.jquery.com/Downloading_jQuery
jQuery API文档：http://docs.jquery.com/Main_Page
jQuery 中国：http://jquery.org.cn/
VisualJQuery.com : http://visualjquery.com/