# React Native Document Scanner
[](https://www.npmjs.com/package/react-native-document-scanner-plugin) [](https://github.com/WebsiteBeaver/react-native-document-scanner-plugin/blob/master/package.json)
This is a React Native plugin that lets you scan documents using Android and iOS. You can use it to create
apps that let users scan notes, homework, business cards, receipts, or anything with a rectangular shape.
| iOS | Android |
| -------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------ |
|  |  |
## Install
```bash
npm install react-native-document-scanner-plugin
```
After installing the plugin, you need to follow the steps below
### iOS
1. iOS requires the following usage description be added and filled out for your app in `Info.plist`:
- `NSCameraUsageDescription` (`Privacy - Camera Usage Description`)
2. Install pods by running
```bash
cd ios && pod install && cd ..
```
### Android
**Note:** You don't need to prompt the user to accept camera permissions for this plugin to work unless you're using another plugin that requires the user to accept camera permissions. See [Android Camera Permissions](#android-camera-permissions).
## Examples
* [Basic Example](#basic-example)
* [Limit Number of Scans](#limit-number-of-scans)
### Basic Example
```jsx
import React, { useState, useEffect } from 'react'
import { Image } from 'react-native'
import DocumentScanner from 'react-native-document-scanner-plugin'
export default () => {
const [scannedImage, setScannedImage] = useState();
const scanDocument = async () => {
// start the document scanner
const { scannedImages } = await DocumentScanner.scanDocument()
// get back an array with scanned image file paths
if (scannedImages.length > 0) {
// set the img src, so we can view the first scanned image
setScannedImage(scannedImages[0])
}
}
useEffect(() => {
// call scanDocument on load
scanDocument()
}, []);
return (
)
}
```
Here's what this example looks like with several items
### Limit Number of Scans
You can limit the number of scans. For example if your app lets a user scan a business
card you might want them to only capture the front and back. In this case you can set
maxNumDocuments to 2. This only works on Android.
```jsx
import React, { useState, useEffect } from 'react'
import { Image } from 'react-native'
import DocumentScanner from 'react-native-document-scanner-plugin'
export default () => {
const [scannedImage, setScannedImage] = useState();
const scanDocument = async () => {
// start the document scanner
const { scannedImages } = await DocumentScanner.scanDocument({
maxNumDocuments: 2
})
// get back an array with scanned image file paths
if (scannedImages.length > 0) {
// set the img src, so we can view the first scanned image
setScannedImage(scannedImages[0])
}
}
useEffect(() => {
// call scanDocument on load
scanDocument()
}, []);
return (
)
}
```
## Documentation
* [`scanDocument(...)`](#scandocument)
* [Interfaces](#interfaces)
* [Enums](#enums)
### scanDocument(...)
```typescript
scanDocument(options?: ScanDocumentOptions | undefined) => Promise
```
Opens the camera, and starts the document scan
| Param | Type |
| ------------- | ------------------------------------------------------------------- |
| **`options`** | ScanDocumentOptions |
**Returns:** Promise<ScanDocumentResponse>
--------------------
### Interfaces
#### ScanDocumentResponse
| Prop | Type | Description |
| ------------------- | --------------------------------------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------- |
| **`scannedImages`** | string[] | This is an array with either file paths or base64 images for the document scan. |
| **`status`** | ScanDocumentResponseStatus | The status lets you know if the document scan completes successfully, or if the user cancels before completing the document scan. |
#### ScanDocumentOptions
| Prop | Type | Description | Default |
| ----------------------- | ----------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ----------------------------------------- |
| **`croppedImageQuality`** | number | The quality of the cropped image from 0 - 100. 100 is the best quality. | : 100 |
| **`maxNumDocuments`** | number | Android only: The maximum number of photos an user can take (not counting photo retakes) | : undefined |
| **`responseType`** | ResponseType | The response comes back in this format on success. It can be the document scan image file paths or base64 images. | : ResponseType.ImageFilePath |
### Enums
#### ScanDocumentResponseStatus
| Members | Value | Description |
| ------------- | ---------------------- | --------------------------------------------------------------------------------------------------------- |
| **`Success`** | 'success' | The status comes back as success if the document scan completes successfully. |
| **`Cancel`** | 'cancel' | The status comes back as cancel if the user closes out of the camera before completing the document scan. |
#### ResponseType
| Members | Value | Description |
| ------------------- | ---------------------------- | ------------------------------------------------------------------------------- |
| **`Base64`** | 'base64' | Use this response type if you want document scan returned as base64 images. |
| **`ImageFilePath`** | 'imageFilePath' | Use this response type if you want document scan returned as inmage file paths. |
## Expo
This plugin doesn't run in Expo Go. It works with Expo, and you can avoid manually changing iOS and Android files by following these steps.
```bash
npx expo install react-native-document-scanner-plugin
```
Add `react-native-document-scanner-plugin` to plugins in `app.json` or `app.config.json`.
```javascript
{
"name": "my expo app",
"plugins": [
[
"react-native-document-scanner-plugin",
{
"cameraPermission": "We need camera access, so you can scan documents"
}
]
]
}
```
```bash
npx expo prebuild
```
or
```bash
eas build
```
## Common Mistakes
* [Android Camera Permissions](#android-camera-permissions)
### Android Camera Permissions
You don't need to request camera permissions unless you're using another camera plugin that adds `` to the application's `AndroidManifest.xml`.
In that case if you don't request camera permissions you get this error
`Error: error - error opening camera: Permission Denial: starting Intent { act=android.media.action.IMAGE_CAPTURE`
Here's an example of how to request camera permissions.
```jsx
import React, { useState, useEffect } from 'react'
import { Platform, PermissionsAndroid, Image, Alert } from 'react-native'
import DocumentScanner from 'react-native-document-scanner-plugin'
export default () => {
const [scannedImage, setScannedImage] = useState();
const scanDocument = async () => {
// prompt user to accept camera permission request if they haven't already
if (Platform.OS === 'android' && await PermissionsAndroid.request(
PermissionsAndroid.PERMISSIONS.CAMERA
) !== PermissionsAndroid.RESULTS.GRANTED) {
Alert.alert('Error', 'User must grant camera permissions to use document scanner.')
return
}
// start the document scanner
const { scannedImages } = await DocumentScanner.scanDocument()
// get back an array with scanned image file paths
if (scannedImages.length > 0) {
// set the img src, so we can view the first scanned image
setScannedImage(scannedImages[0])
}
}
useEffect(() => {
// call scanDocument on load
scanDocument()
}, []);
return (
)
}
```