Json Angular2应用程序没有';我看不到服务
我正在构建一个Angular2应用程序,并试图从本地json文件获取数据。 问题是我创建的服务被应用程序忽略了。控制台或终端中都没有错误、警告或其他内容 index.htmlJson Angular2应用程序没有';我看不到服务,json,http,angular,observable,Json,Http,Angular,Observable,我正在构建一个Angular2应用程序,并试图从本地json文件获取数据。 问题是我创建的服务被应用程序忽略了。控制台或终端中都没有错误、警告或其他内容 index.html <!DOCTYPE html> <html> <head> <base href="/"> <title>My app</title> <meta charset="UTF-8"> <meta name="viewport" cont
<!DOCTYPE html>
<html>
<head>
<base href="/">
<title>My app</title>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet" href="app/assets/flex.css">
<link rel="stylesheet" href="app/assets/styles.css">
<!-- Polyfill(s) for older browsers -->
<script src="node_modules/core-js/client/shim.min.js"></script>
<script src="node_modules/zone.js/dist/zone.js"></script>
<script src="node_modules/reflect-metadata/Reflect.js"></script>
<script src="node_modules/systemjs/dist/system.src.js"></script>
<script src="systemjs.config.js"></script>
<script>
System.import('app').catch(function(err){ console.error(err); });
</script>
</head>
<body>
<my-app>OLOLOading...</my-app>
</body>
</html>
<div class="releases-component">
<div *ngFor="let release of releases | async">
<h3>Name: {{releases.name}}</h3>
<h4>Name: {{releases.instrument}}</h4>
</div>
</div>
releases.component.html
<!DOCTYPE html>
<html>
<head>
<base href="/">
<title>My app</title>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet" href="app/assets/flex.css">
<link rel="stylesheet" href="app/assets/styles.css">
<!-- Polyfill(s) for older browsers -->
<script src="node_modules/core-js/client/shim.min.js"></script>
<script src="node_modules/zone.js/dist/zone.js"></script>
<script src="node_modules/reflect-metadata/Reflect.js"></script>
<script src="node_modules/systemjs/dist/system.src.js"></script>
<script src="systemjs.config.js"></script>
<script>
System.import('app').catch(function(err){ console.error(err); });
</script>
</head>
<body>
<my-app>OLOLOading...</my-app>
</body>
</html>
<div class="releases-component">
<div *ngFor="let release of releases | async">
<h3>Name: {{releases.name}}</h3>
<h4>Name: {{releases.instrument}}</h4>
</div>
</div>
哪里做错了?如果使用异步管道,则不需要使用显式subscribe(),因为异步自动订阅可观察对象。试试这个:
export class ReleasesComponent implements OnInit {
releases: Observable<Array<string>>;
constructor(private releasesService: ReleasesService) {
}
ngOnInit() {
this.releases = this.releasesService.getReleases();
}
}
导出类ReleasesComponent在NIT上实现{
释放:可见;
构造函数(私有ReleaseService:ReleaseService){
}
ngOnInit(){
this.releases=this.releaseService.getReleases();
}
}
您是否在订阅中登录了控制台?它记录了什么吗?你是说在map方法中?每当我在服务中尝试Console.log时都会忽略它否我的意思是订阅<代码>this.releasesService.getReleases().subscribe(releases=>{this.releases=releases;})代码>为什么要执行this.releases=releasesService.getReleases()代码>在构造函数中,因为您是在ngOnInit
中订阅的。这可能是一个原因吧?似乎我的releases.service.ts在保存时没有转换为releases.service.js
export class ReleasesComponent implements OnInit {
releases: Observable<Array<string>>;
constructor(private releasesService: ReleasesService) {
}
ngOnInit() {
this.releases = this.releasesService.getReleases();
}
}