ngx-file-helpers

Angular File Helpers

Installation

Add the package to your application.

npm install --save ngx-file-helpers

Demo

https://stackblitz.com/edit/ngx-file-helpers-demo

Breaking changes

Here's a list of the breaking changes upon the 11.0 release:

• Angular (core/common) version 17.0.0 or greater is a peer dependency;

Here's a list of the breaking changes upon the 10.0 release:

• Angular (core/common) version 16.0.0 or greater is a peer dependency;

Here's a list of the breaking changes upon the 9.0 release:

• Angular (core/common) version 15.0.0 or greater is a peer dependency;

Here's a list of the breaking changes upon the 8.0 release:

• Angular (core/common) version 14.0.0 or greater is a peer dependency;

Here's a list of the breaking changes upon the 7.0 release:

• Angular (core/common) version 13.0.0 or greater is a peer dependency;

Here's a list of the breaking changes upon the 6.0 release:

• Angular (core/common) version 12.0.0 or greater is a peer dependency;

Here's a list of the breaking changes upon the 5.0 release:

• Angular (core/common) version 11.0.0 or greater is a peer dependency;

Here's a list of the breaking changes upon the 4.0 release:

• Angular (core/common) version 9.1.0 or greater is a peer dependency;

Here's a list of the breaking changes upon the 3.0 release:

• Angular (core/common) version 8.2.0 or greater is a peer dependency;

Here's a list of the breaking changes upon the 2.0 release:

• Angular (core/common) version 7.2.0 or greater is a peer dependency;
• The module name has changed to NgxFileHelpersModule;
• Read mode is not anymore bound using the directive name but the [readMode] property;
• The lastModifiedDate property doesn't exist anymore on the ReadFile interface.

Getting started

Import the file helpers module to your application module.

import { BrowserModule } from '@angular/platform-browser';
import { NgModule } from '@angular/core';
import { NgxFileHelpersModule } from 'ngx-file-helpers';

import { AppComponent } from './app.component';

@NgModule({
  declarations: [AppComponent],
  imports: [
    BrowserModule,
    NgxFileHelpersModule
  ],
  bootstrap: [AppComponent]
})
export class AppModule { }

File Picker

Add the file picker directive to an element, like a button.

<button type="button" ngxFilePicker>Browse</button>

Select how the file should be read; by default the mode is dataUrl.

<button type="button" ngxFilePicker [readMode]="readMode">Browse</button>

Bind to the filePick event to get the picked file from the $event variable.

<button
  type="button"
  ngxFilePicker
  (filePick)="file = $event">
  Browse
</button>

Use the optional accept attribute to indicate the types of files that the control can select.

<button
  type="button"
  ngxFilePicker
  accept="image/*"
  (filePick)="file = $event">
  Browse
</button>

Use the optional multiple attribute to indicate whether the user can pick more than one file.

<button
  type="button"
  ngxFilePicker
  accept="image/*"
  multiple
  (filePick)="file = $event">
  Browse
</button>

Use the option filter attribute to specify a callback that you would implemented to filter if the file should be read or ignored.

<button
  type="button"
  ngxFilePicker
  accept="image/*"
  multiple
  [filter]="ignoreTooBigFile"
  (filePick)="file = $event">
  Browse
</button>

export class MyComponent {
  ...
  ignoreTooBigFile(file: File): boolean {
    return file.size < 100000;
  }
}

The directive also has a reset() method that unset the selected file. This is useful if you want to force the filePick event to trigger again even if the user has picked the same file. The directive is exported as ngxFilePicker so you can select is using a ViewChild decorator.

<button
  ngxFilePicker
  #myFilePicker="ngxFilePicker">
  Browse
</button>

export class MyComponent {
  ...
  @ViewChild('myFilePicker')
  private filePicker: FilePickerDirective;
  ...

  onReadEnd(fileCount: number) {
    this.status = `Read ${fileCount} file(s) on ${new Date().toLocaleTimeString()}.`;
    this.filePicker.reset();
  }
}

There are three more events that can be listened to:

• readStart: triggered when the directive start to read files.
• readError: triggered when the directive has encountered an error reading a file; this typically occurs when dropping a folder
• readEnd: triggered when the directive has read all the files.

readStart emits the number of files ($event variable) to be read. readError emits an object containing the file and the error that occurred. readEnd emits the number of files that have been successfully read.

In some cases you may want to filter files before reading them. You could use a special input argument filter which takes a function which should return true file to be read or false to stop reading.

export class MyComponent {
  ...

  filterFileBeforeReading(file) {
    // file is a native browser File
    // skip files which are >25mb
    return file.size < 25 * 1000 * 1000;
  }
}

<button
  type="button"
  ngxFilePicker
  accept="*"
  multiple
  [filter]="filterFileBeforeReading"
  (filePick)="file = $event">
  Browse
</button>

File Dropzone

Add the file dropzone directive to an element, like a div.

<div ngxFileDropzone>Drop a file in this zone.</div>

Select how the file should be read; by default the mode is dataUrl.

<div ngxFileDropzone [readMode]="readMode">Drop a file in this zone.</div>

Bind to the fileDrop event to get the dropped file from the $event variable.

<div
  ngxFileDropzone
  (fileDrop)="file = $event">
  Drop a file in this zone.
</div>

The directive is exported as ngxFileDropzone so you can select is using a ViewChild decorator. You can use the same filter attribute and readStart, readEnd events (see the FilePicker directive).

ReadFile

The read file implements the following interface:

interface ReadFile {
  name: string;
  size: number;
  type: string;
  readMode: ReadMode;
  content?: any;
  underlyingFile: File; // https://developer.mozilla.org/en-US/docs/Web/API/File
}

ReadMode

Available read modes are exposed through the ReadMode enum:

enum ReadMode {
  ArrayBuffer,
  BinaryString,
  DataURL,
  Text
  Skip,
}

A new read mode has been introduced to ensure the directive skips reading the file. This is particularly important when uploading large files as the FileReader used behind the scenes cannot handle that case by default. Reading the underlying file is left to the directive consumer as the content property will be undefined for ReadMode.Skip.