Implementing Syncfusion Angular Uploader

The Syncfusion Angular Uploader (

ejs-uploader

) is a full-featured file upload component that supports asynchronous uploads, chunk uploading of large files, drag-and-drop, clipboard paste, directory upload, file validation, templates, form integration, JWT authentication, and comprehensive event handling.

Component Overview

The Syncfusion Angular Uploader provides:

Async upload modes: Auto upload (default) or manual upload with action buttons
Chunk upload: Split large files into configurable byte-size chunks with retry logic
Sequential upload: Process files one at a time to reduce server traffic
File sources: Browse dialog, drag-and-drop, clipboard paste, directory selection
Validation: File type (extensions), min/max size, custom count limits, duplicate prevention
Templates: Customize the file list item structure; build fully custom upload UIs
Form support: HTML form submission, template-driven forms (ngModel), reactive forms (FormGroup)
Accessibility: WCAG 2.2, Section 508, keyboard navigation, screen reader support
Localization: Customize all static text via L10n

Documentation & Navigation Guide

Getting Started

📄 Read: references/getting-started.md

Installation of
```
@syncfusion/ej2-angular-inputs
```
Package setup, CSS imports, and Angular standalone component usage
Adding the
```
<ejs-uploader>
```
component
Configuring async settings (saveUrl, removeUrl)
Handling success and failure events
Adding a custom drop area

Asynchronous Upload

📄 Read: references/async-upload.md

Multiple and single file upload modes (
```
multiple
```
property)
Save action configuration and server-side handling
Remove action and
```
postRawFile
```
usage
Auto upload vs manual upload (
```
autoUpload
```
property)
Sequential upload (
```
sequentialUpload
```
)
Preloaded files (
```
files
```
property)
Adding custom HTTP headers to upload requests

Chunk Upload

📄 Read: references/chunk-upload.md

Enabling chunk upload via
```
asyncSettings.chunkSize
```
Pause, resume, and cancel chunk uploads
Retry configuration (
```
retryCount
```
,
```
retryAfterDelay
```
)
```
chunkSuccess
```
and
```
chunkFailure
```
events
Server-side chunk assembly implementation

File Validation

📄 Read: references/validation.md

Restricting file types with
```
allowedExtensions
```
Min/max file size constraints (
```
minFileSize
```
,
```
maxFileSize
```
)
Limiting upload count via the
```
selected
```
event
Preventing duplicate file uploads
MIME type validation before upload
Image/* validation on drag-and-drop

File Sources

📄 Read: references/file-sources.md

Paste images from clipboard
Directory (folder) upload with
```
directoryUpload
```
Drag-and-drop with built-in and custom drop areas
Custom drop area styling (
```
.e-upload-drag-hover
```
)
Triggering file browse from an external button

Templates & Custom UI

📄 Read: references/templates-and-custom-ui.md

File list template with the
```
template
```
property
Building a completely custom upload UI (hiding default list with
```
showFileList
```
)
Customizing action buttons with HTML elements (
```
buttons
```
property)
Customizing the progress bar appearance
Preview images before uploading
Resize images before uploading to server

Form Integration

📄 Read: references/form-integration.md

Using Uploader inside HTML forms (synchronous submission)
Template-driven forms with
```
ngModel
```
Reactive forms with
```
FormGroup
```
Required field validation (
```
required
```
attribute)
Reset behavior with form reset

Styling & Appearance

📄 Read: references/styling-and-appearance.md

Customizing the uploader wrapper dimensions
Styling the browse button
Customizing the drop area text
Customizing the file list container
Hiding the default drop area
CSS class reference for key Uploader elements

Accessibility & Localization

📄 Read: references/accessibility-and-localization.md

WCAG 2.2, Section 508, keyboard shortcuts
Screen reader and RTL support
Localizing all static labels and messages with L10n

Advanced How-To Patterns

📄 Read: references/advanced-patterns.md

Upload files programmatically with the
```
upload()
```
method
Invisible (background) upload
Adding additional form data with
```
customFormData
```
JWT authentication for upload/remove requests
Show confirmation dialog before removing files
Get total size of selected files
Sort selected files in the file list
Open and edit uploaded files from the server
Convert uploaded images to binary format

API Reference

📄 Read: references/api.md

Complete properties, methods, and events reference
AsyncSettingsModel, ButtonsPropsModel, FilesPropModel
All event argument types and their fields

Quick Start Example

Minimal file uploader with async upload (Angular 21+ standalone):

typescript

import { Component } from '@angular/core';
import { UploaderModule } from '@syncfusion/ej2-angular-inputs';

@Component({
  imports: [UploaderModule],
  standalone: true,
  selector: 'app-root',
  template: `
    <ejs-uploader
      [asyncSettings]="asyncSettings"
      [autoUpload]="false"
      (success)="onSuccess($event)"
      (failure)="onFailure($event)">
    </ejs-uploader>
  `
})
export class AppComponent {
  public asyncSettings = {
    saveUrl: 'https://your-api/upload/save',
    removeUrl: 'https://your-api/upload/remove'
  };

  onSuccess(args: any): void {
    console.log('Upload operation:', args.operation, 'File:', args.file.name);
  }

  onFailure(args: any): void {
    console.error('Upload failed:', args.file.name);
  }
}

CSS Theme Setup (

styles.css

css

@import 'node_modules/@syncfusion/ej2-base/styles/material3.css';
@import 'node_modules/@syncfusion/ej2-buttons/styles/material3.css';
@import 'node_modules/@syncfusion/ej2-inputs/styles/material3.css';
@import 'node_modules/@syncfusion/ej2-popups/styles/material3.css';
@import 'node_modules/@syncfusion/ej2-angular-inputs/styles/material3.css';

Common Patterns

Pattern 1: Auto Upload with Drag-and-Drop

typescript

// Automatically uploads dropped or browsed files
<ejs-uploader
  [asyncSettings]="asyncSettings"
  [dropArea]="dropElement"
  [multiple]="true"
  (success)="onSuccess($event)">
</ejs-uploader>

Pattern 2: Chunk Upload for Large Files

typescript

<ejs-uploader
  [asyncSettings]="chunkSettings"
  (chunkSuccess)="onChunkSuccess($event)"
  (chunkFailure)="onChunkFailure($event)">
</ejs-uploader>

// In component:
chunkSettings = {
  saveUrl: 'https://your-api/upload/save',
  removeUrl: 'https://your-api/upload/remove',
  chunkSize: 500000  // 500 KB chunks
};

Pattern 3: Validated Upload (Type + Size)

typescript

<ejs-uploader
  [asyncSettings]="asyncSettings"
  allowedExtensions=".jpg,.png,.pdf"
  [minFileSize]="1024"
  [maxFileSize]="5000000">
</ejs-uploader>

Pattern 4: Preloaded Files

typescript

<ejs-uploader
  [asyncSettings]="asyncSettings"
  [files]="preloadedFiles">
</ejs-uploader>

// In component:
preloadedFiles = [
  { name: 'report', size: 200000, type: '.pdf' },
  { name: 'photo', size: 500000, type: '.jpg' }
];

Pattern 5: JWT-Authenticated Upload

typescript

<ejs-uploader
  [asyncSettings]="asyncSettings"
  (uploading)="addAuthHeader($event)"
  (removing)="addAuthHeader($event)">
</ejs-uploader>

addAuthHeader(args: any): void {
  args.currentRequest.setRequestHeader('Authorization', `Bearer ${this.token}`);
}

Key Properties

Property	Type	Default	Purpose
`[asyncSettings]`	AsyncSettingsModel	`{saveUrl:'',removeUrl:''}`	Server save/remove URLs and chunk config
`[autoUpload]`	boolean	`true`	Upload immediately on file selection
`[multiple]`	boolean	`true`	Allow selecting multiple files
`[allowedExtensions]`	string	`''`	Comma-separated allowed extensions (e.g., `.jpg,.png` )
`[minFileSize]`	number	`0`	Minimum file size in bytes
`[maxFileSize]`	number	`30000000`	Maximum file size in bytes (~28.6 MB)
`[files]`	FilesPropModel[]	`[]`	Preloaded files from server
`[dropArea]`	string \| HTMLElement	`null`	Custom drop target element or selector
`[directoryUpload]`	boolean	`false`	Enable folder/directory upload
`[sequentialUpload]`	boolean	`false`	Upload files one at a time
`[showFileList]`	boolean	`true`	Show/hide default file list
`[template]`	any	`null`	Custom file list item template
`[buttons]`	ButtonsPropsModel	`{browse,clear,upload}`	Customize button text/HTML
`[enabled]`	boolean	`true`	Enable or disable the component
`[cssClass]`	string	`''`	Additional CSS classes on root element
`[enableRtl]`	boolean	`false`	Right-to-left rendering
`[enableHtmlSanitizer]`	boolean	`true`	Prevent XSS in filenames
`[dropEffect]`	DropEffect	`'Default'`	Drag effect: Copy, Move, Link, None

Key Events

Event	When it Fires	Key Args
`(selected)`	Files selected or dropped	`filesData` , `cancel` , `modifiedFilesData`
`(uploading)`	Before each file upload starts	`fileData` , `currentRequest` , `customFormData` , `cancel`
`(success)`	Upload or remove succeeds	`file` , `operation` ( `upload` \| `remove` ), `event`
`(failure)`	Upload or remove fails	`file` , `operation` , `event`
`(progress)`	Upload progress	`file` , `event` (loaded, total)
`(removing)`	Before file remove request	`filesData` , `postRawFile` , `currentRequest`
`(beforeRemove)`	Before remove confirmation	`filesData` , `cancel`
`(beforeUpload)`	Before upload process	`fileData` , `customFormData`
`(change)`	File list changes	`file`
`(clearing)`	Before clear all action	`cancel`
`(chunkSuccess)`	Each chunk uploads OK	`chunkIndex` , `totalChunk` , `chunkSize` , `file`
`(chunkFailure)`	Each chunk fails	`chunkIndex` , `totalChunk` , `chunkSize` , `file` , `cancel`
`(chunkUploading)`	Before each chunk upload	`fileData` , `currentRequest` , `customFormData`
`(pausing)`	Chunk upload paused	`file` , `chunkIndex`
`(resuming)`	Chunk upload resumed	`file` , `chunkIndex`
`(canceling)`	Upload canceled	`file`
`(fileListRendering)`	Before each file item renders	`element` , `fileInfo`
`(actionComplete)`	All files processed	`fileData`
`(created)`	Component initialized	—

Key Methods

Method	Purpose
`upload(files?, custom?)`	Programmatically start upload for selected or specific files
`remove(fileData?, custom?, postRawFile?)`	Remove a file from list or server
`cancel(fileData?)`	Cancel an in-progress chunk upload
`pause(fileData?, custom?)`	Pause a chunk upload
`resume(fileData?, custom?)`	Resume a paused chunk upload
`retry(fileData?, fromCanceledStage?, custom?)`	Retry a failed or canceled upload
`clearAll()`	Clear all files from the list
`getFilesData(index?)`	Get file data array shown in the list
`createFileList(fileData)`	Programmatically create file list items
`sortFileList(filesData?)`	Sort file list alphabetically
`bytesToSize(bytes)`	Convert bytes to human-readable KB/MB string
`destroy()`	Destroy the component and detach events

Common Use Cases

Use Case 1: Profile Photo Upload

multiple="false"

allowedExtensions=".jpg,.png,.gif,.webp"

maxFileSize=5000000

Use
```
selected
```
event to preview before upload
Auto upload with progress indicator

Use Case 2: Document Upload Portal

Multiple files,

allowedExtensions=".pdf,.doc,.docx,.xlsx"

Chunk upload for large files with pause/resume
Sequential upload to manage server load

Use Case 3: Image Gallery Batch Upload

Multiple files, directory upload enabled
Preview thumbnails using
```
selected
```
event + FileReader
Sort by file name before upload

Use Case 4: Secure File Upload (API-Authenticated)

JWT token injected via
```
uploading
```
event header
Custom
```
customFormData
```
to pass metadata
Server validates token before saving

Use Case 5: Form with Required File

```
autoUpload=false
```
, synchronous form submission
Required attribute validation with
```
data-required-message
```
Template-driven or reactive form binding

Next Steps

Getting Started → Install package and render basic uploader
Async Upload → Configure save/remove URLs and upload modes
Validation → Add extension and size constraints
Chunk Upload → Handle large files with pause/resume
Templates → Customize file list appearance
Form Integration → Bind to Angular forms
Advanced Patterns → JWT auth, programmatic upload, custom UI
API Reference → Full properties, methods, events list

For detailed implementation, start with references/getting-started.md

syncfusion-angular-uploader

NPX Install

Tags

SKILL.md Content

Implementing Syncfusion Angular Uploader

Component Overview

Documentation & Navigation Guide

Getting Started

Asynchronous Upload

Chunk Upload

File Validation

File Sources

Templates & Custom UI

Form Integration

Styling & Appearance

Accessibility & Localization

Advanced How-To Patterns

API Reference

Quick Start Example

Common Patterns

Pattern 1: Auto Upload with Drag-and-Drop

Pattern 2: Chunk Upload for Large Files

Pattern 3: Validated Upload (Type + Size)

Pattern 4: Preloaded Files

Pattern 5: JWT-Authenticated Upload

Key Properties

Key Events

Key Methods

Common Use Cases

Next Steps