EmberJS中的find（）和filter（function（）{return true;}）之间的区别 [英] Difference between find() and filter(function(){return true;}) in EmberJS

问题描述

我正在制作一个简单的餐厅菜单。我需要根据当前当前类别来过滤菜肴清单。问题在于 this.store.filter（...）方法的行为异常。它不返回任何内容...

I'm working on a simple restaurant menu. And I need to filter list of dishes accordingly to the category in which we are now in current moment. The problem is in a strange behaviour of a this.store.filter(...) method. It doesn't return anything...

我要像这样使用它：

App.DishRoute = Ember.Route.extend({
  model: function (param) {
    return this.store.filter('dish', function(dish) {
      return dish.get('category_id') == param.category_id;
    });
  }
});

但出于测试目的，我使用的是 this.store.filter（ 'dish'，function（）{return true;}）; 在我的示例中，此处为 http ：//jsbin.com/AcoHeNA/43/ 。

but for the test purpose I'm using this.store.filter('dish', function() {return true;}); in my example here http://jsbin.com/AcoHeNA/43/.

请查看代码，告诉我我做错了什么，或者告诉我应该怎么做

Please review the code and tell me what am I doing wrong or show me the way I should filter the data.

推荐答案

store.filter 不查询服务器，它只是过滤存储中已经加载的数据。对于您而言，由于您一刻都不加载数据，因此过滤器将返回空结果。您可以调用 this.store.find（'dish'）; 进行修复，以从服务器加载数据，因此，任何 filter（'dish'， ...）将被更新。

store.filter doesn't query the server, it just filter the already loaded data in the store. In your case because you don't load data in any moment, the filter will return a empty result. You can fix it calling this.store.find('dish'); to load data from the server, so any filter('dish', ...) will be updated.

App.DishRoute = Ember.Route.extend({
  model: function (param) {
    console.log(param.dish_id);

    // pre load the data
    this.store.find('dish');
    // filter the prefetch data, when update the filter when new data are loaded
    return this.store.filter('dish', function(){return true;});    
  }
});

这是更新的jsbin http://jsbin.com/akeJOTah/1/edit

This is the updated jsbin http://jsbin.com/akeJOTah/1/edit

这是最常用商店的概述方法：

This is an overview of the most used store methods:

1. store.find（'dish'）=>发送带有/ dishes的请求


2. store.find（'dish'，1）=>发送带有/ dishes / 1
的请求

3. store.find（'dish'，{名称：'some'}）=>发送带有/ dishes？name = some
的请求

4. store.filter（'dish'，function（）{...}）=>客户端过滤，不发送请求，只需过滤存储中存在的数据


5. store.filter（'dish'，function（）{...}，{foo：'bar'}）=>运行查找查询（项目3）并执行客户端过滤


6. store.all（'dish'）=>不发送请求，仅获取存储在商店中的所有数据

1. store.find('dish') => send a request with /dishes
2. store.find('dish', 1) => send a request with /dishes/1
3. store.find('dish', { name: 'some' }) => send a request with /dishes?name=some
4. store.filter('dish', function() { ... }) => client side filtering, don't send a request, just filter the data present in the store
5. store.filter('dish', function() { ... }, { foo: 'bar' }) => run the find with query (item 3) and perform a client side filtering
6. store.all('dish') => don't send request, just get all the data loaded in the store

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