我有这个模块,它将外部库与额外的逻辑组件化,而不直接将<script>标记添加到index.html中:

import 'http://external.com/path/file.js'
//import '../js/file.js'

@Component({
    selector: 'my-app',
    template: `
        <script src="http://iknow.com/this/does/not/work/either/file.js"></script>
        <div>Template</div>`
})
export class MyAppComponent {...}

我注意到ES6规范的导入是静态的,并且是在TypeScript编译期间解析的,而不是在运行时。

总之,让它变得可配置,这样file。js就会从CDN或本地文件夹加载? 如何告诉Angular 2动态加载脚本?


当前回答

@ rahull -kumar的解决方案对我来说很好,但我想在我的typescript中调用我的javascript函数

foo.myFunctions() // works in browser console, but foo can't be used in typescript file

我通过在我的typescript中声明它来修复它:

import { Component } from '@angular/core';
import { ScriptService } from './script.service';
declare var foo;

现在,我可以在typcript文件的任何地方调用foo

其他回答

Angular的通用解决方案;在加载播放视频的脚本之前,我需要等待页面上的特定元素。

import {Inject, Injectable, PLATFORM_ID} from '@angular/core';
import {isPlatformBrowser} from "@angular/common";

@Injectable({
  providedIn: 'root'
})
export class ScriptLoaderService {

  constructor(
    @Inject(PLATFORM_ID) private platformId: Object,
  ) {
  }

  load(scriptUrl: string) {
    if (isPlatformBrowser(this.platformId)) {
      let node: any = document.createElement('script');
      node.src = scriptUrl;
      node.type = 'text/javascript';
      node.async = true;
      node.charset = 'utf-8';
      document.getElementsByTagName('head')[0].appendChild(node);
    }
  }
}

这可能有用。这段代码动态地将<script>标记附加到单击按钮时的html文件头部。

const url = 'http://iknow.com/this/does/not/work/either/file.js';

export class MyAppComponent {
    loadAPI: Promise<any>;

    public buttonClicked() {
        this.loadAPI = new Promise((resolve) => {
            console.log('resolving promise...');
            this.loadScript();
        });
    }

    public loadScript() {
        console.log('preparing to load...')
        let node = document.createElement('script');
        node.src = url;
        node.type = 'text/javascript';
        node.async = true;
        node.charset = 'utf-8';
        document.getElementsByTagName('head')[0].appendChild(node);
    }
}

Angular有防止用户直接干扰html输出的逻辑。所以你必须让Angular通过在Angular中给出那个方向来注入标签。json文件。

首先,您必须获取脚本文件。有两种方法:

下载脚本文件(例如。somelibrary.js)

把它放在资产文件夹中 把脚本的相对路径,放到angular的“scripts”部分。json文件:

"scripts": [
  "src/assets/somelibrary.js"
]

使用npm/yarn安装脚本:

把脚本的相对路径,放到angular的“scripts”部分。json文件:

"scripts": [
  "./node_modules/somelibrary/dist/somelibrary.min.js"
]

这个解决方案对我很有效:

1)创建一个名为URLLoader的新类

export class URLLoader {
  constructor() {

  }

  loadScripts() {

    const dynamicScripts = [
      'URL 1',
      'URL 2',
      'URL n'
    ];

    for (let i = 0; i < dynamicScripts.length; i++) {
      const node = document.createElement('script');
      node.src = dynamicScripts[i];
      node.type = 'text/javascript';
      node.async = false;
      node.charset = 'utf-8';
      document.getElementsByTagName('app-root')[0].appendChild(node);
    }
  }

}

2)扩展类URLLoader并从组件类中调用loadScripts方法

export class AppComponent extends URLLoader implements OnInit {  

   constructor(){}

   ngOnInit() {
   super.loadScripts();
   }

}
import { Injectable } from '@angular/core';
import * as $ from 'jquery';

interface Script {
    src: string;
    loaded: boolean;
}

@Injectable()
export class ScriptLoaderService {
    public _scripts: Script[] = [];

    /**
     * @deprecated
     * @param tag
     * @param {string} scripts
     * @returns {Promise<any[]>}
     */
    load(tag, ...scripts: string[]) {
        scripts.forEach((src: string) => {
            if (!this._scripts[src]) {
                this._scripts[src] = { src: src, loaded: false };
            }
        });

        const promises: any[] = [];
        scripts.forEach(src => promises.push(this.loadScript(tag, src)));

        return Promise.all(promises);
    }

    /**
     * Lazy load list of scripts
     * @param tag
     * @param scripts
     * @param loadOnce
     * @returns {Promise<any[]>}
     */
    loadScripts(tag, scripts, loadOnce?: boolean) {
        debugger;
        loadOnce = loadOnce || false;

        scripts.forEach((script: string) => {
            if (!this._scripts[script]) {
                this._scripts[script] = { src: script, loaded: false };
            }
        });

        const promises: any[] = [];
        scripts.forEach(script => promises.push(this.loadScript(tag, script, loadOnce)));

        return Promise.all(promises);
    }

    /**
     * Lazy load a single script
     * @param tag
     * @param {string} src
     * @param loadOnce
     * @returns {Promise<any>}
     */
    loadScript(tag, src: string, loadOnce?: boolean) {
        debugger;
        loadOnce = loadOnce || false;

        if (!this._scripts[src]) {
            this._scripts[src] = { src: src, loaded: false };
        }

        return new Promise((resolve, _reject) => {
            // resolve if already loaded
            if (this._scripts[src].loaded && loadOnce) {
                resolve({ src: src, loaded: true });
            } else {
                // load script tag
                const scriptTag = $('<script/>')
                    .attr('type', 'text/javascript')
                    .attr('src', this._scripts[src].src);

                $(tag).append(scriptTag);

                this._scripts[src] = { src: src, loaded: true };
                resolve({ src: src, loaded: true });
            }
        });
    }

    reloadOnSessionChange() {
        window.addEventListener('storage', function(data) {
            if (data['key'] === 'token' && data['oldValue'] == null && data['newValue']) {
                document.location.reload();
            }
        });
    }
}