Dynamic Script Loading in Angular: A Solution

Introduction:

In Angular applications, the need to include external scripts can arise. However, adding

Dynamic Script Loading:

To dynamically load scripts, we can employ the following steps:

1. Create a Script Store: Establish an array of objects called ScriptStore, which holds script paths and unique names for dynamic loading.
2. Inject the Script Service: Implement the ScriptService as an injectable Angular service that manages script loading.
3. Load Scripts Method: Define a load method in ScriptService to load scripts dynamically. This method takes script names as parameters and returns a promise.
4. Load Script Implementation: Within the load method, check if the script is already loaded. If not, create a
5. Inject and Invoke the Service: Inject ScriptService into the component or service where you need to load scripts. Call the load method to load the desired scripts.

Example Code:

Below is a sample implementation of the script store and service:

interface Scripts {
  name: string;
  src: string;
}

// Script store with sample script definitions
export const ScriptStore: Scripts[] = [
  { name: 'filepicker', src: 'https://api.filestackapi.com/filestack.js' },
  { name: 'rangeSlider', src: '../../../assets/js/ion.rangeSlider.min.js' }
];

@Injectable()
export class ScriptService {
  private scripts: any = {};

  constructor() {
    ScriptStore.forEach((script: any) => {
      this.scripts[script.name] = {
        loaded: false,
        src: script.src
      };
    });
  }

  load(...scripts: string[]) {
    var promises: any[] = [];
    scripts.forEach((script) => promises.push(this.loadScript(script)));
    return Promise.all(promises);
  }

  loadScript(name: string) {
    return new Promise((resolve, reject) => {
      // Check if script is already loaded
      if (this.scripts[name].loaded) {
        resolve({ script: name, loaded: true, status: 'Already Loaded' });
      } else {
        let script = document.createElement('script');
        script.type = 'text/javascript';
        script.src = this.scripts[name].src;
        script.onload = () => {
          this.scripts[name].loaded = true;
          resolve({ script: name, loaded: true, status: 'Loaded' });
        };
        script.onerror = (error: any) => resolve({ script: name, loaded: false, status: 'Loaded' });
        document.getElementsByTagName('head')[0].appendChild(script);
      }
    });
  }
}

Usage:

In the component or service where you wish to load scripts dynamically, inject the ScriptService. Then, within a method, invoke the load method like this:

this.script.load('filepicker', 'rangeSlider').then(data => {
  console.log('script loaded ', data);
}).catch(error => console.log(error));

In this example, both filepicker and rangeSlider scripts will be loaded dynamically. You can now configure the ScriptStore to load scripts from either a CDN or a local folder as needed.