从http获取json服务的角度

Question

我有用于Angular的js，可从http获取json服务，并在html上使用{{post.title}}来获取数据并将其发布到html。

数据未显示在html页上-使用代码笔。

var app = angular.module("blogApp", []); 
app.controller("mainCtrl",      function($scope) {
$scope.posts = []; 
let postsUrl ="https://jsonplaceholder.typicode.com/posts"
    getPosts().then(posts =>{
        $scope.posts = posts.slice(3);
        $scope.$apply();
    });

    function getPosts(){
        return fetch(postsUrl).then(res=>res.json());
    }

}）;

Answer 1

我看过您共享的Codepen。 因此，Ricky是您对angularJS的新手，我建议您从这里阅读与angular 1相关的文档： Angular JS-文档

现在满足您的要求，您需要调用一个外部API并使用结果中的数据。 为此，您必须了解angularJS中的$http ： $ http文档

来到代码中，angular支持依赖注入。 就像fetch(postsUrl)函数在做什么一样，您共享的代码对我来说还是一个谜。 声明在哪里？

简而言之，实现应清晰易读。 这是我重构的：

var app = angular.module("blogApp", []); //here you defined the ng-app module

//you are initializing a controller, you need to inject $http for calling the API 
app.controller("mainCtrl", function($scope, $http) {

        //Declaration of the posts object
        $scope.posts = [];

        //Onetime initialization of the API Endpoint URL
        let postsUrl ="https://jsonplaceholder.typicode.com/posts";

        //A method for getting the posts
        function getPosts(){

           //We are calling API endpoint via GET request and waiting for the result which is a promise 
           //todo: Read about the Promises
           //A promise return 2 things either a success or a failure callback, you need to handle both. 
           //The first one is success and the second one is a failure callback
           //So in general the structure is as $http.get(...).then(successCallback, failureCallback)  
            $http.get(postsUrl).then(function(response){

               //In promises you get data in the property data, for a test you can log response like console.log(response)
               var data = response.data;

               $scope.posts = data; //Storing the data in the posts variable

                //Note: you don't need to call the $scope.$apply() because your request is with in the angular digest process. 
                //All the request which are outside the angular scope required a $apply()
            }, function(err){
               //log the err response here or show the notification you want to do
            });
        }

        //The final step is to call that function and it is simple
        getPosts();         

});

来到第二部分以显示数据。 您必须使用ng-repeat文档，它是ng-repeat="var item in collection track by $index" 。 它的文档在这里ng-repeat

因此，您的html应该采用以下结构：

<div  ng-repeat="var post in posts track by $index"> 
    {{post.userid}}
    {{post.id}}
    {{post.title}}
    {{post.body}}
</div> 

现在，您可以学习和实施。