Javascript AngularJS计数ID等于的JSON数组中的项目数
我可以使用以下方法获得JSON数组中的文章总数: Home.htmlJavascript AngularJS计数ID等于的JSON数组中的项目数,javascript,json,angularjs,Javascript,Json,Angularjs,我可以使用以下方法获得JSON数组中的文章总数: Home.html <div ng-controller="pfcArticleCountCtrl">Number of Articles {{articlecount.length}} items</div> }])) Services.js // Articles by ID pfcServices.factory('pfcArticles', ['$resource', function ($resource) {
<div ng-controller="pfcArticleCountCtrl">Number of Articles {{articlecount.length}} items</div>
}]))
Services.js
// Articles by ID
pfcServices.factory('pfcArticles', ['$resource', function ($resource) {
return $resource('https://myrestcall.net/tables/articles/:articleID', { articleID: '@id' },
{
'update': { method:'PATCH'}
}
);
}]);
但我也希望按类别显示文章的数量。下面是一个JSON返回示例:
[
{
"id": "66D5069C-DC67-46FC-8A51-1F15A94216D4",
"articletitle": "artilce1",
"articlecategoryid": 1,
"articlesummary": "article 1 summary. "
},
{
"id": "66D5069C-DC67-46FC-8A51-1F15A94216D5",
"articletitle": "artilce2",
"articlecategoryid": 2,
"articlesummary": "article 2 summary. "
},
{
"id": "66D5069C-DC67-46FC-8A51-1F15A94216D6",
"articletitle": "artilce3",
"articlecategoryid": 3,
"articlesummary": "article 3 summary. "
},
{
"id": "66D5069C-DC67-46FC-8A51-1F15A94216D7",
"articletitle": "artilce4",
"articlecategoryid": 1,
"articlesummary": "article 3 summary. "
},
]
在本例中,总计数为4,但对于类别1,应为2。我想在页面上显示如下:
第1(2)类
第2(1)类
第3(1)类
文章总数(4)
如何按类别计算文章数量?首先对数组进行排序
var data=[]代码>(您的数据)
data.sort(排序);
函数排序(a,b){
如果(a.articlecategoryidb.articlecategoryid)
返回1;
返回0;
}
然后计算重复的值
var current = null;
var cnt = 0;
for (var i = 0; i < data.length; i++) {
if (data[i].articlecategoryid != current) {
if (cnt > 0) {
document.write('Category'+current+'-->'+cnt+ ' times<br>');
}
current = data[i].articlecategoryid;
cnt = 1;
} else {
cnt++;
}
}
if (cnt > 0) {
document.write('Category'+current+'-->'+cnt+ ' times');
}
var电流=null;
var-cnt=0;
对于(变量i=0;i0){
document.write('Category'+current+'-->'+cnt+'times
');
}
当前=数据[i]。articlecategoryid;
cnt=1;
}否则{
cnt++;
}
}
如果(cnt>0){
document.write('Category'+current+'-->'+cnt+'times');
}
参见中的示例,您可以使用reduce创建一个对象,其中cat id作为名称,count作为值:
$scope.articleByCat = articles.reduce(function (prev, item) {
if ( !! prev[item.articlecategoryid]) {
//category already exist -> increment
prev[item.articlecategoryid]++;
} else {
//category does not exist -> init
prev[item.articlecategoryid] = 1;
}
return prev;
}, {});
通过作用域公开它,并通过ng repat显示它
<div ng-app='article' ng-controller='ArticleController'>
<ul>
<li ng-repeat='(key, value) in articleByCat'>Category {{key}} : {{value}}</li>
</ul>
</div>
- 类别{{key}}:{{value}
A工作你的问题是什么?我看不到任何问号……这不是问题所在。您需要循环查看结果以计算所有类别。只有在这之后,在文章的末尾添加了angulars视图模型问题。它如何最适合angulars的输出?例如,$scope.count=document.write('Category'+current+'-->'+cnt+'times');
$scope.articleByCat = articles.reduce(function (prev, item) {
if ( !! prev[item.articlecategoryid]) {
//category already exist -> increment
prev[item.articlecategoryid]++;
} else {
//category does not exist -> init
prev[item.articlecategoryid] = 1;
}
return prev;
}, {});
<div ng-app='article' ng-controller='ArticleController'>
<ul>
<li ng-repeat='(key, value) in articleByCat'>Category {{key}} : {{value}}</li>
</ul>
</div>