1、 查看一个store支持那些APIs

var store = new some.Datastore();

var features = store.getFeatures();

for(var i in features){

console.log("Store supports feature: " + i);

}

2、 测试一个对象是不是一个item

var store = new some.Datastore();

if(store.isItem(someObject)){

console.log("Object was an item.");

}else{

console.log("Object was NOT an item.");

}

3、 列举一个item的所有属性

var store = new some.Datastore();

...

//Assume that someItem is an item we got from a load.

var attributes = store.getAttributes(someItem);

for(var i = 0; i < attributes.length; i++){

console.log("Item has attribute; " + attributes[i]);

}

4、 测试一个item是否包含特定的属性

var store = new some.Datastore();

...

//Assume that someItem is an item we got from a load.

var attributes = store.getAttributes(someItem);

for(var i = 0; i < attributes.length; i++){

console.log("Item has attribute; " + attributes[i]);

}

5、 得到一个item的label

var store = new some.Datastore();

...

//Assume that someItem is an item we got from a load.

var label = store.getLabel(someItem);

console.log("item has label: " + label);

//其实一个item的label也是一个item的属性，只不过是一个特殊的属性。在json的开始部分：label:”name” 这个就声明了，item的name属性就是item的label，所以通过getLabel就得到了name属性，也就等同于getValue(item,”name”);

6、得到一个store的所有数据

var pantryStore = new dojo.data.JsonItemStore({url: "pantry_items.json" } );

//Define the onComplete callback to write COMPLETED to the page when the fetch has finished returning items.

var done = function(items,request){

document.appendChild(document.createTextNode("COMPLETED"));

}

//Define the callback that appends a textnode into the document each time an item is returned.

gotItem = function(item,request) {

document.appendChild(document.createTextNode(pantryStore.getValue(item,"name"));

document.appendChild(document.createElement("br"));

}

//Define a simple error handler.

var gotError = function(error,request){

alert("The request to the store Failed. " + error);

}

//Invoke the search

pantryStore.fetch({onComplete: done,onItem: gotItem,onError: gotError});

//这里onComplete和onItem同时使用的时候onComplete的items参数是null,这点请注意。

6、 通过一个标识得到一个item

var pantryStore = new dojo.data.JsonItemStore({url: "pantry_items.json" } );

var pepperItem = pantryStore.getItemByIdentity("pepper");

if (pepperItem !== null){

alert(&apos;Pepper is in aisle &apos; + pantryStore.getValue(pepperItem,"aisle");

}

//这个标识在json的开头部分有声明, identifier: &apos;name&apos; ，也就是说item的name属性是标识。

7、 通过条件获取数据

jsonItemStore.fetch({

queryOptions: {ignoreCase: true}, //忽略大小写

query: { name: "*pepper*",aisle: "Spices" },//name 和 aisle是属性的名称

onComplete:

...

});

8、 嵌套定义item

一个item可以包括多个子item就像一棵树一样。使用reference可以关联子节点。通过getValues()方法可以得到孩子节点的数组。

9、 分页

var store = new dojo.data.JsonItemStore({url: "pantryStore.json" });

var pageSize = 10;

var request = null;

var outOfItems = false;

var onNext = function(){

if(!outOfItems){

request.start += pageSize;

store.fetch(request);

}

};

var onPrevIoUs = function(){

if (request.start > 0){

request.start -= pageSize;

store.fetch(request);

}

}

var itemsLoaded = function(items,request){

if (items.length < pageSize){

outOfItems = true;

}else{

outOfItems = false;

}

...

}

request = store.fetch({onComplete: itemsLoaded,start: 0; count: pageSize});

10、 排序

var store = new dojo.data.JsonItemStore({url: "pantryStore.json"});

var sortKeys = [

{attribute: "aisle",descending: true},

{attribute: "name",descending: false}

];

store.fetch({

sort: sortKeys;

onComplete:

...

});

//When onComplete is called,the array of items passed into it

//should be sorted according to the denoted sort array.
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