atomreadstore.js

这是一个ajax的例子大家好好的看看就是一个鱼眼的效果

				element: this.doc.getElementsByTagName("feed")[0],
				store: this,
				_attribs: {}
			};
			this._parseItem(this._feedMetaData);
		}
		return this._feedMetaData._attribs[attribute] || defaultValue;
	},

	_initItem: function(item){
		// summary:
		//		Initializes an item before it can be parsed.
		if(!item._attribs){
			item._attribs = {};
		}
	},

	_fetchItems: function(request, fetchHandler, errorHandler) {
		// summary:
		//		Retrieves the items from the Atom XML document.
		var url = this._getFetchUrl(request);
		if(!url){
			errorHandler(new Error("No URL specified."));
			return;
		}
		var localRequest = (!this.sendQuery ? request : null); // use request for _getItems()

		var _this = this;
		var docHandler = function(data){
			_this.doc = data;
			var items = _this._getItems(data, localRequest);
			var query = request.query;
			if(query) {
				if(query.id) {
					items = dojo.filter(items, function(item){
						return (_this.getValue(item, "id") == query.id);
					});
				} else if(query.category){
					items = dojo.filter(items, function(entry) {
						var cats = _this.getValues(entry, "category");
						if(!cats){
							return false;
						}
						return dojo.some(cats, "return item.term=='"+query.category+"'");
					});
				}
			}

			if (items && items.length > 0) {
				fetchHandler(items, request);
			}
			else {
				fetchHandler([], request);
			}
		};

		if (this.doc) {
			docHandler(this.doc);
		}else{
			var getArgs = {
				url: url,
				handleAs: "xml"//,
			//	preventCache: true
			};
			var getHandler = dojo.xhrGet(getArgs);
			getHandler.addCallback(docHandler);

			getHandler.addErrback(function(data){
				errorHandler(data, request);
			});
		}
	},

	_getFetchUrl: function(request){
		if(!this.sendQuery){
			return this.url;
		}
		var query = request.query;
		if(!query){
			return this.url;
		}
		if(dojo.isString(query)){
			return this.url + query;
		}
		var queryString = "";
		for(var name in query){
			var value = query[name];
			if(value){
				if(queryString){
					queryString += "&";
				}
				queryString += (name + "=" + value);
			}
		}
		if(!queryString){
			return this.url;
		}
		//Check to see if the URL already has query params or not.
		var fullUrl = this.url;
		if(fullUrl.indexOf("?") < 0){
			fullUrl += "?";
		}else{
			fullUrl += "&";
		}
		return fullUrl + queryString;
	},

	_getItems: function(document, request) {
		// summary:
		//		Parses the document in a first pass
		if(this._items){
			return this._items;
		}
		var items = [];
		var nodes = [];
		
		if(document.childNodes.length < 1){
			this._items = items;
			console.log("dojox.data.AtomReadStore: Received an invalid Atom document. Check the content type header");
			return items;
		}
		
		var feedNodes = dojo.filter(document.childNodes, "return item.tagName && item.tagName.toLowerCase() == 'feed'");

		var query = request.query;

		if(!feedNodes || feedNodes.length != 1){
			console.log("dojox.data.AtomReadStore: Received an invalid Atom document, number of feed tags = " + (feedNodes? feedNodes.length : 0));
			return items;
		}

		nodes = dojo.filter(feedNodes[0].childNodes, "return item.tagName && item.tagName.toLowerCase() == 'entry'");

		if(request.onBegin){
			request.onBegin(nodes.length);
		}

		for(var i = 0; i < nodes.length; i++){
			var node = nodes[i];
			if(node.nodeType != 1 /*ELEMENT_NODE*/){
				continue;
			}
			items.push(this._getItem(node));
		}
		this._items = items;
		return items;
	},

	close: function(/*dojo.data.api.Request || keywordArgs || null */ request){
		 //	summary:
		 //		See dojo.data.api.Read.close()
	},

/* internal API */

	_getItem: function(element){
		return {
			element: element,
			store: this
		};
	},

	_parseItem: function(item) {
		var attribs = item._attribs;
		var _this = this;
		var text, type;

		function getNodeText(node){
			var txt = node.textContent || node.innerHTML || node.innerXML;			
			if(!txt && node.childNodes[0]){
				var child = node.childNodes[0];
				if (child && (child.nodeType == 3 || child.nodeType == 4)) {
					txt = node.childNodes[0].nodeValue;
				}
			}
			return txt;
		}
		function parseTextAndType(node) {
			return {text: getNodeText(node),type: node.getAttribute("type")};
		}
		dojo.forEach(item.element.childNodes, function(node){
			var tagName = node.tagName ? node.tagName.toLowerCase() : "";
			switch(tagName){
				case "title":
					attribs[tagName] = {
						text: getNodeText(node),
						type: node.getAttribute("type")
					}; break;
				case "subtitle":
				case "summary":
				case "content":
					attribs[tagName] = parseTextAndType(node);
					break;
				case "author":
					var nameNode ,uriNode;
					dojo.forEach(node.childNodes, function(child){
						if(!child.tagName){
							return;
						}
						switch(child.tagName.toLowerCase()){
							case "name":nameNode = child;break;
							case "uri": uriNode = child; break;
						}
					});
					var author = {};
					if(nameNode && nameNode.length == 1){
						author.name = getNodeText(nameNode[0]);
					}
					if(uriNode && uriNode.length == 1){
						author.uri = getNodeText(uriNode[0]);
					}
					attribs[tagName] = author;
					break;
				case "id": attribs[tagName] = getNodeText(node); break;
				case "updated": attribs[tagName] = dojo.date.stamp.fromISOString(getNodeText(node) );break;
				case "published": attribs[tagName] = dojo.date.stamp.fromISOString(getNodeText(node));break;
				case "category":
					if(!attribs[tagName]){
						attribs[tagName] = [];
					}
					attribs[tagName].push({scheme:node.getAttribute("scheme"), term: node.getAttribute("term")});
					break;
				case "link":
					if(!attribs[tagName]){
						attribs[tagName] = [];
					}
					var link = {
						rel: node.getAttribute("rel"),
						href: node.getAttribute("href"),
						type: node.getAttribute("type")};
					attribs[tagName].push(link);

					if(link.rel == "alternate") {
						attribs["alternate"] = link;
					}
					break;
				default:
					break;
			}
		});
	},

	_unescapeHTML : function(text) {
		//Replace HTML character codes with their unencoded equivalents, e.g. &#8217; with '
		text = text.replace(/&#8217;/m , "'").replace(/&#8243;/m , "\"").replace(/&#60;/m,">").replace(/&#62;/m,"<").replace(/&#38;/m,"&");
		return text;
	},

	_assertIsItem: function(/* item */ item){
		//	summary:
		//		This function tests whether the item passed in is indeed an item in the store.
		//	item: 
		//		The item to test for being contained by the store.
		if(!this.isItem(item)){ 
			throw new Error("dojox.data.AtomReadStore: Invalid item argument.");
		}
	},

	_assertIsAttribute: function(/* attribute-name-string */ attribute){
		//	summary:
		//		This function tests whether the item passed in is indeed a valid 'attribute' like type for the store.
		//	attribute: 
		//		The attribute to test for being contained by the store.
		if(typeof attribute !== "string"){ 
			throw new Error("dojox.data.AtomReadStore: Invalid attribute argument.");
		}
	}
});
dojo.extend(dojox.data.AtomReadStore,dojo.data.util.simpleFetch);

}