src/data.js

   1 var expando = "jQuery" + now(), uuid = 0, windowData = {};
   2 var emptyObject = {};
   3
   4 jQuery.extend({
   5         cache: {},
   6
   7         expando:expando,
   8
   9         // The following elements throw uncatchable exceptions if you
  10         // attempt to add expando properties to them.
  11         noData: {
  12                 "embed": true,
  13                 "object": true,
  14                 "applet": true
  15         },
  16
  17         data: function( elem, name, data ) {
  18                 if ( elem.nodeName && jQuery.noData[elem.nodeName.toLowerCase()] ) {
  19                         return;
  20                 }
  21
  22                 elem = elem == window ?
  23                         windowData :
  24                         elem;
  25
  26                 var id = elem[ expando ], cache = jQuery.cache, thisCache;
  27
  28                 // Handle the case where there's no name immediately
  29                 if ( !name && !id ) {
  30                         return null;
  31                 }
  32
  33                 // Compute a unique ID for the element
  34                 if ( !id ) {
  35                         id = ++uuid;
  36                 }
  37
  38                 // Avoid generating a new cache unless none exists and we
  39                 // want to manipulate it.
  40                 if ( cache[ id ] ) {
  41                         thisCache = cache[ id ];
  42                 } else if ( typeof data === "undefined" ) {
  43                         thisCache = emptyObject;
  44                 } else {
  45                         thisCache = cache[ id ] = {};
  46                 }
  47
  48                 // Prevent overriding the named cache with undefined values
  49                 if ( data !== undefined ) {
  50                         elem[ expando ] = id;
  51                         thisCache[ name ] = data;
  52                 }
  53
  54                 return name ? 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
 105                 var parts = key.split(".");
 106                 parts[1] = parts[1] ? "." + parts[1] : "";
 107
 108                 if ( value === undefined ) {
 109                         var data = this.triggerHandler("getData" + parts[1] + "!", [parts[0]]);
 110
 111                         if ( data === undefined && this.length ) {
 112                                 data = jQuery.data( this[0], key );
 113                         }
 114                         return data === undefined && parts[1] ?
 115                                 this.data( parts[0] ) :
 116                                 data;
 117                 } else {
 118                         return this.trigger("setData" + parts[1] + "!", [parts[0], value]).each(function(){
 119                                 jQuery.data( this, key, value );
 120                         });
 121                 }
 122         },
 123
 124         removeData: function( key ){
 125                 return this.each(function(){
 126                         jQuery.removeData( this, key );
 127                 });
 128         }
 129 });