How to load external scripts dynamically in Angular?

Question

I have this module which componentize the external library together with additional logic without adding the

Answer 1

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}
     */
    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}
     */
    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}
     */
    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 = $('