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 ( typeof name === "object" ) {
  41                         elem[ expando ] = id;
  42                         thisCache = cache[ id ] = jQuery.extend(true, {}, name);
  43                 } else if ( cache[ id ] ) {
  44                         thisCache = cache[ id ];
  45                 } else if ( typeof data === "undefined" ) {
  46                         thisCache = emptyObject;
  47                 } else {
  48                         thisCache = cache[ id ] = {};
  49                 }
  50
  51                 // Prevent overriding the named cache with undefined values
  52                 if ( data !== undefined ) {
  53                         elem[ expando ] = id;
  54                         thisCache[ name ] = data;
  55                 }
  56
  57                 return typeof name === "string" ? thisCache[ name ] : thisCache;
  58         },
  59
  60         removeData: function( elem, name ) {
  61                 if ( elem.nodeName && jQuery.noData[elem.nodeName.toLowerCase()] ) {
  62                         return;
  63                 }
  64
  65                 elem = elem == window ?
  66                         windowData :
  67                         elem;
  68
  69                 var id = elem[ expando ], cache = jQuery.cache, thisCache = cache[ id ];
  70
  71                 // If we want to remove a specific section of the element's data
  72                 if ( name ) {
  73                         if ( thisCache ) {
  74                                 // Remove the section of cache data
  75                                 delete thisCache[ name ];
  76
  77                                 // If we've removed all the data, remove the element's cache
  78                                 if ( jQuery.isEmptyObject(thisCache) ) {
  79                                         jQuery.removeData( elem );
  80                                 }
  81                         }
  82
  83                 // Otherwise, we want to remove all of the element's data
  84                 } else {
  85                         // Clean up the element expando
  86                         try {
  87                                 delete elem[ expando ];
  88                         } catch( e ) {
  89                                 // IE has trouble directly removing the expando
  90                                 // but it's ok with using removeAttribute
  91                                 if ( elem.removeAttribute ) {
  92                                         elem.removeAttribute( expando );
  93                                 }
  94                         }
  95
  96                         // Completely remove the data cache
  97                         delete cache[ id ];
  98                 }
  99         }
 100 });
 101
 102 jQuery.fn.extend({
 103         data: function( key, value ){
 104                 if ( typeof key === "undefined" && this.length ) {
 105                         return jQuery.data( this[0] );
 106
 107                 } else if ( typeof key === "object" ) {
 108                         return this.each(function() {
 109                                 jQuery.data( this, key );
 110                         });
 111                 }
 112
 113                 var parts = key.split(".");
 114                 parts[1] = parts[1] ? "." + parts[1] : "";
 115
 116                 if ( value === undefined ) {
 117                         var data = this.triggerHandler("getData" + parts[1] + "!", [parts[0]]);
 118
 119                         if ( data === undefined && this.length ) {
 120                                 data = jQuery.data( this[0], key );
 121                         }
 122                         return data === undefined && parts[1] ?
 123                                 this.data( parts[0] ) :
 124                                 data;
 125                 } else {
 126                         return this.trigger("setData" + parts[1] + "!", [parts[0], value]).each(function(){
 127                                 jQuery.data( this, key, value );
 128                         });
 129                 }
 130         },
 131
 132         removeData: function( key ){
 133                 return this.each(function(){
 134                         jQuery.removeData( this, key );
 135                 });
 136         }
 137 });