src/data.js

   1 var expando = "jQuery" + now(), uuid = 0, windowData = {};
   2
   3 jQuery.extend({
   4         cache: {},
   5
   6         expando:expando,
   7
   8         // The following elements throw uncatchable exceptions if you
   9         // attempt to add expando properties to them.
  10         noData: {
  11                 "embed": true,
  12                 "object": true,
  13                 "applet": true
  14         },
  15
  16         data: function( elem, name, data ) {
  17                 if ( elem.nodeName && jQuery.noData[elem.nodeName.toLowerCase()] ) {
  18                         return;
  19                 }
  20
  21                 elem = elem == window ?
  22                         windowData :
  23                         elem;
  24
  25                 var id = elem[ expando ], cache = jQuery.cache, thisCache;
  26
  27                 if ( !id && typeof name === "string" && data === undefined ) {
  28                         return null;
  29                 }
  30
  31                 // Compute a unique ID for the element
  32                 if ( !id ) {
  33                         id = ++uuid;
  34                 }
  35
  36                 // Avoid generating a new cache unless none exists and we
  37                 // want to manipulate it.
  38                 if ( typeof name === "object" ) {
  39                         elem[ expando ] = id;
  40                         thisCache = cache[ id ] = jQuery.extend(true, {}, name);
  41
  42                 } else if ( !cache[ id ] ) {
  43                         elem[ expando ] = id;
  44                         cache[ id ] = {};
  45                 }
  46
  47                 thisCache = cache[ id ];
  48
  49                 // Prevent overriding the named cache with undefined values
  50                 if ( data !== undefined ) {
  51                         thisCache[ name ] = data;
  52                 }
  53
  54                 return typeof name === "string" ? thisCache[ name ] : thisCache;
  55         },
  56
  57         removeData: function( elem, name ) {
  58                 if ( elem.nodeName && jQuery.noData[elem.nodeName.toLowerCase()] ) {
  59                         return;
  60                 }
  61
  62                 elem = elem == window ?
  63                         windowData :
  64                         elem;
  65
  66                 var id = elem[ expando ], cache = jQuery.cache, thisCache = cache[ id ];
  67
  68                 // If we want to remove a specific section of the element's data
  69                 if ( name ) {
  70                         if ( thisCache ) {
  71                                 // Remove the section of cache data
  72                                 delete thisCache[ name ];
  73
  74                                 // If we've removed all the data, remove the element's cache
  75                                 if ( jQuery.isEmptyObject(thisCache) ) {
  76                                         jQuery.removeData( elem );
  77                                 }
  78                         }
  79
  80                 // Otherwise, we want to remove all of the element's data
  81                 } else {
  82                         // Clean up the element expando
  83                         try {
  84                                 delete elem[ expando ];
  85                         } catch( e ) {
  86                                 // IE has trouble directly removing the expando
  87                                 // but it's ok with using removeAttribute
  88                                 if ( elem.removeAttribute ) {
  89                                         elem.removeAttribute( expando );
  90                                 }
  91                         }
  92
  93                         // Completely remove the data cache
  94                         delete cache[ id ];
  95                 }
  96         }
  97 });
  98
  99 jQuery.fn.extend({
 100         data: function( key, value ) {
 101                 if ( typeof key === "undefined" && this.length ) {
 102                         return jQuery.data( this[0] );
 103
 104                 } else if ( typeof key === "object" ) {
 105                         return this.each(function() {
 106                                 jQuery.data( this, key );
 107                         });
 108                 }
 109
 110                 var parts = key.split(".");
 111                 parts[1] = parts[1] ? "." + parts[1] : "";
 112
 113                 if ( value === undefined ) {
 114                         var data = this.triggerHandler("getData" + parts[1] + "!", [parts[0]]);
 115
 116                         if ( data === undefined && this.length ) {
 117                                 data = jQuery.data( this[0], key );
 118                         }
 119                         return data === undefined && parts[1] ?
 120                                 this.data( parts[0] ) :
 121                                 data;
 122                 } else {
 123                         return this.trigger("setData" + parts[1] + "!", [parts[0], value]).each(function() {
 124                                 jQuery.data( this, key, value );
 125                         });
 126                 }
 127         },
 128
 129         removeData: function( key ) {
 130                 return this.each(function() {
 131                         jQuery.removeData( this, key );
 132                 });
 133         }
 134 });
 135
 136 var removeExpando = function( elem ) {
 137         delete elem[ expando ];
 138 };
 139
 140 try {
 141         var div = document.createElement("div");
 142         div[ expando ] = true;
 143         delete div[ expando ];
 144
 145 } catch( e ) {
 146         // IE has trouble directly removing the expando
 147         // but it's ok with using removeAttribute
 148         removeExpando = function( elem ) {
 149                 if ( elem.removeAttribute ) {
 150                         elem.removeAttribute( expando );
 151                 }
 152         };
 153 }