Instructions for using CSS operations in jQuery

Instructions for using CSS operations in jQuery_jquery

WBOY

Release： 2016-05-16 19:12:41

Original

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I just took a look at the source code of jQuery, and the operating ideas about CSS and className are indeed very good and worth learning from.
The definition part of jQuery.className.has is implemented using regular expressions. In fact, if you directly use the indexOf method of the String object in Javascript to process it, it will be more efficient than using regular expressions, so

Copy code The code is as follows:

The definition of jQuery.className.has can be improved to: 
 has: function ( t, c ) { 
 t = t.className || t; 
 t = " " t " "; 
 c = " " c " "; 
 return t.indexOf(c) >-1;  
 }  

The excerpts about the operation of CSS and className in the original code are as follows:

Copy code The code is as follows:

  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;  
  }, 