尝试使用 ng2-charts 时出现 404 错误

Question

我在尝试使 ng2-charts 工作时遇到问题。我在 GitHub 和这里阅读了许多类似的帖子，但到目前为止没有任何成功。 错误是：

Error: (SystemJS) XHR error (404 Not Found) loading http://localhost:9823/ng2-charts
    Error: XHR error (404 Not Found) loading http://localhost:9823/ng2-charts
        at XMLHttpRequest.wrapFn [as _onreadystatechange] (http://localhost:9823/lib/zone.js/dist/zone.js:698:29)
        at ZoneDelegate.invokeTask (http://localhost:9823/lib/zone.js/dist/zone.js:265:35)
        at Zone.runTask (http://localhost:9823/lib/zone.js/dist/zone.js:154:47)
        at XMLHttpRequest.ZoneTask.invoke (http://localhost:9823/lib/zone.js/dist/zone.js:335:33)
    Error loading http://localhost:9823/ng2-charts as "ng2-charts" from http://localhost:9823/lib/spa/app.module.js
        at XMLHttpRequest.wrapFn [as _onreadystatechange] (http://localhost:9823/lib/zone.js/dist/zone.js:698:29)
        at ZoneDelegate.invokeTask (http://localhost:9823/lib/zone.js/dist/zone.js:265:35)
        at Zone.runTask (http://localhost:9823/lib/zone.js/dist/zone.js:154:47)
        at XMLHttpRequest.ZoneTask.invoke (http://localhost:9823/lib/zone.js/dist/zone.js:335:33)
    Error loading http://localhost:9823/ng2-charts as "ng2-charts" from http://localhost:9823/lib/spa/app.module.js

我的 app.module.ts：

import {ChartsModule} from 'ng2-charts';
[...]
@NgModule({
    imports: [
        BrowserModule,
        FormsModule,
        HttpModule,
        routing,
        AccountModule,
        ChartsModule
    ] [...]

我的系统js.config.js

(function (global) {
    System.config({
        paths: {
            // paths serve as alias
            'npm:': 'lib/'
        },
        // map tells the System loader where to look for things
        map: {
            // our app is within the app folder
            app: 'lib/spa',
            // angular bundles
            '@angular/core': 'npm:@angular/core/bundles/core.umd.js',
            '@angular/common': 'npm:@angular/common/bundles/common.umd.js',
            '@angular/compiler': 'npm:@angular/compiler/bundles/compiler.umd.js',
            '@angular/platform-browser': 'npm:@angular/platform-browser/bundles/platform-browser.umd.js',
            '@angular/platform-browser-dynamic': 'npm:@angular/platform-browser-dynamic/bundles/platform-browser-dynamic.umd.js',
            '@angular/http': 'npm:@angular/http/bundles/http.umd.js',
            '@angular/router': 'npm:@angular/router/bundles/router.umd.js',
            '@angular/forms': 'npm:@angular/forms/bundles/forms.umd.js',
            // other libraries
            'rxjs': 'npm:rxjs',
            'angular-in-memory-web-api': 'npm:angular-in-memory-web-api/bundles/in-memory-web-api.umd.js',
            'ng2-charts': 'npm:ng2-charts',
        },
        // packages tells the System loader how to load when no filename and/or no extension
        packages: {
            app: {
                main: './main.js',
                defaultExtension: 'js'
            },
            rxjs: {
                defaultExtension: 'js'
            },
            'angular2-in-memory-web-api': {
                main: './index.js',
                defaultExtension: 'js'
            },
            'ng2-charts': {
                defaultExtension: 'js'
            }

        }
    });
})(this);

我对 Angular2 还很陌生，所以我将非常感谢任何有关如何使图表工作的提示。 当然，一开始我是通过 bower 安装 chart.js 和 ng2-charts 的，我包括了

<script src="~/lib/chart.js/dist/Chart.js"></script>

在我的 Index.cshtml 文件中。

Answer 1

在 ./src/systemjs.config.js 文件的以下配置中的 map 下添加 'ng2-charts': 'npm:ng2-charts/bundles/ng2-charts.umd.min.js' 行。我正在使用 Angular 4.3.4 和 ng2-charts 1.6.0，这对我来说非常适合。

/**  * System configuration for Angular samples  * Adjust as necessary for your application needs.  */ (function (global) {   System.config({
    paths: {
      // paths serve as alias
      'npm:': 'node_modules/'
    },
    // map tells the System loader where to look for things
    map: {
      // our app is within the app folder
      'app': 'app',

      // angular bundles
      '@angular/core': 'npm:@angular/core/bundles/core.umd.js',
      '@angular/common': 'npm:@angular/common/bundles/common.umd.js',
      '@angular/compiler': 'npm:@angular/compiler/bundles/compiler.umd.js',
      '@angular/platform-browser': 'npm:@angular/platform-browser/bundles/platform-browser.umd.js',
      '@angular/platform-browser-dynamic': 'npm:@angular/platform-browser-dynamic/bundles/platform-browser-dynamic.umd.js',
      '@angular/http': 'npm:@angular/http/bundles/http.umd.js',
      '@angular/router': 'npm:@angular/router/bundles/router.umd.js',
      '@angular/forms': 'npm:@angular/forms/bundles/forms.umd.js',

      // other libraries
      'rxjs':                      'npm:rxjs',
      'angular-in-memory-web-api': 'npm:angular-in-memory-web-api/bundles/in-memory-web-api.umd.js',
      'ng2-charts': 'npm:ng2-charts/bundles/ng2-charts.umd.min.js'
    },
    // packages tells the System loader how to load when no filename and/or no extension
    packages: {
      app: {
        defaultExtension: 'js',
        meta: {
          './*.js': {
            loader: 'systemjs-angular-loader.js'
          }
        }
      },
      rxjs: {
        defaultExtension: 'js'
      }
    }   }); })(this);

Answer 2

在 System.config.js 中更改为，

 map: {
 'ng2-charts': 'npm:ng2-charts'
}

packages: {
  main: 'ng2-charts.js',
  defaultExtension: 'js'
}

然后将其导入为，

import { ChartsModule } from 'ng2-charts/ng2-charts';