abp/docs/en/UI/Angular/File-Utils-Service.md

File Utils Service

FileUtilsService is an Angular service designed to provide utility methods related to file operations. The service has a downloadBlob function, which is used for downloading blobs as files within the context of a web application.

Usage

To make use of the FileUtilsService in your Angular application, follow the steps below:

Injection: Firstly, ensure that the service is injected into the component or any other Angular entity where you wish to use it.

import { FileUtilsService } from '@abp/ng.core';

constructor(private fileUtils: FileUtilsService) { }
// or
// private fileUtils   = inject(FileUtilsService)

Downloading a Blob:

Once you have the service injected, you can use the downloadBlob method to initiate the download of blob data as a file. For instance:

someMethod() {
  const myBlob = new Blob(["Hello, World!"], { type: "text/plain" });
  this.fileUtils.downloadBlob(myBlob, "hello.txt");
}

Permissions & Considerations:

Ensure that you have appropriate permissions and user interactions before triggering a download. Since downloadBlob initiates a download programmatically, it's best to tie this action to direct user interactions, such as button clicks, to prevent unexpected behaviors or browser restrictions.

DOCUMENT Token in Service

Angular, being a platform-agnostic framework, is designed to support not only browser-based applications but also other environments like server-side rendering (SSR) through Angular Universal. This design philosophy introduces challenges when accessing global browser-specific objects like window or document directly. To address this, Angular provides a DOCUMENT token that can be used to inject the document object into Angular entities like components and services.