How to use react-native-fs - 10 common examples

itemTestsuite.att('name', suiteName);
            itemTestsuite.att('tests', nbrTests);
            itemTestsuite.att('failures', nbrFailures);
            itemTestsuite.att('timestamp', "2016-01-22T14:40:44.874443-05:00");//TODO use real timestamp

        }
        // export unit tests results
        let xmlString = rootXml.end({
            pretty: true,
            indent: '  ',
            newline: '\n',
        });

        // write the unit tests reports
        const path =  RNFS.MainBundlePath + "/tests.xml";
        await RNFS.writeFile(path, xmlString, 'utf8');
        
        //using console.log output is not shown in Release builds. using console.warn
        console.warn(xmlString);
        console.warn('__REALM_JS_TESTS_COMPLETED__');
        if (failingTests.length !== 0) {
            console.error('\n\nREALM_FAILING_TESTS\n');
            console.error(failingTests);
        } 
    }
    catch (e) {
        console.error(e);
    }
    finally {
        console.warn("Realm Tests App finished. Exiting. Disable this to debug the app locally");
        RNExitApp.exitApp();
    }

import * as RNFS from 'react-native-fs';


// get a list of files and directories in the main bundle
RNFS.readDir(RNFS.MainBundlePath) // On Android, use "RNFS.DocumentDirectoryPath" (MainBundlePath is not defined)
  .then((result) => {
    console.log('GOT RESULT', result);

    // stat the first file
    return Promise.all([RNFS.stat(result[0].path), result[0].path]);
  })
  .then((statResult) => {
    if (statResult[0].isFile()) {
      // if we have a file, read it
      return RNFS.readFile(statResult[1], 'utf8');
    }

    return 'no file';
  })
  .then((contents) => {
    // log the file contents

import React from 'react'

import fs from 'react-native-fs'
import ImageViewer from 'react-native-image-zoom-viewer'
import {
  Animated,
  Easing,
  CameraRoll
} from 'react-native'

declare var global

const psnineFolder = fs.DocumentDirectoryPath + '/psnine'

fs.stat(psnineFolder).then(data => {
  const isDirectory = data.isDirectory()
  if (!isDirectory) {
    fs.unlink(psnineFolder).catch(() => {}).then(() => fs.mkdir(psnineFolder))
  }
}).catch(() => {
  fs.mkdir(psnineFolder).catch(err => console.log(err, 'ImageViewer:line#27'))
})

const onSave = (image) => {
  // console.log(image, psnineFolder + '/' + image.split('/').pop())
  const result = CameraRoll.saveToCameraRoll(image)
  return result.then((url) => {
    global.toast('保存成功')
    return url

import React from 'react'

import fs from 'react-native-fs'
import ImageViewer from 'react-native-image-zoom-viewer'
import {
  Animated,
  Easing,
  CameraRoll
} from 'react-native'

declare var global

const psnineFolder = fs.DocumentDirectoryPath + '/psnine'

fs.stat(psnineFolder).then(data => {
  const isDirectory = data.isDirectory()
  if (!isDirectory) {
    fs.unlink(psnineFolder).catch(() => {}).then(() => fs.mkdir(psnineFolder))
  }
}).catch(() => {
  fs.mkdir(psnineFolder).catch(err => console.log(err, 'ImageViewer:line#27'))
})

const onSave = (image) => {
  // console.log(image, psnineFolder + '/' + image.split('/').pop())
  const result = CameraRoll.saveToCameraRoll(image)
  return result.then((url) => {
    global.toast('保存成功')
    return url
  }).catch(err => global.toast('保存失败: ' + err.toString()))
}

import {
  ToastAndroid,
  View,
  Animated,
  Easing,
  StatusBar,
  Text
} from 'react-native'

import fs from 'react-native-fs'
import { ViewPagerZoom } from 'react-native-image-zoom'
import PhotoView from 'react-native-photo-view'

declare var global

const psnineFolder = fs.ExternalStorageDirectoryPath + '/psnine'
console.log('==========================>')
fs.stat(psnineFolder).then(data => {
  const isDirectory = data.isDirectory()
  if (!isDirectory) {
    fs.unlink(psnineFolder).catch(() => { }).then(() => fs.mkdir(psnineFolder))
  }
}).catch(() => {
  fs.mkdir(psnineFolder).catch(err => console.log(err, 'ImageViewer:line#27'))
})

const onSave = (image) => {
  // console.log(image, psnineFolder + '/' + image.split('/').pop())
  const result = fs.downloadFile({
    fromUrl: image,
    toFile: psnineFolder + '/' + image.split('/').pop()
  })

export default async function photosTask (dispatch, failedImages) {
  // console.log('FAILED IMAGES:', failedImages)
  console.log('running photos task')
  BackgroundTimer.start() // This requests some background time from the OS

  // Start IPFS
  const path = RNFS.DocumentDirectoryPath
  await IPFS.createNodeWithDataDir(path)
  await IPFS.startNode()

  // Get a list of the jobs already in the queue
  // const existingJobs = await queue.getJobs(true)

  // Query for any new photos, add jobs to queue
  const photos = await queryPhotos()
  // PushNotificationIOS.presentLocalNotification({
  //   alertBody: 'fetch of ' + photos.length + ' photos',
  //   userInfo: {}
  // })
  for (const photo of photos) {
    const multipartData = await IPFS.addImageAtPath(photo.node.image.path, photo.node.image.thumbPath)
    await RNFS.unlink(photo.node.image.path)
    await RNFS.unlink(photo.node.image.thumbPath)

async function _deleteConfiguration(): Promise < void > {
  try {
    const configVersions : Array < Object > = await Database.getConfigVersions();
    const clearVersions: Array < Object > = [];

    if (configVersions == null) {
      return;
    }

    for (let i = 0; i < configVersions.length; i++) {
      try {
        const dir = CONFIG_SUBDIRECTORIES[configVersions[i].type];
        await RNFS.unlink(CONFIG_DIRECTORY + dir + configVersions[i].name);
      } catch (e) {
        // do nothing - file doesn't exist
      }

      clearVersions.push({
        name: configVersions[i].name,
        type: configVersions[i].type,
        version: 0,
      });
    }

    await Database.updateConfigVersions(clearVersions);
    await RNFS.unlink(CONFIG_DIRECTORY);
  } catch (err) {
    console.log('Error accessing database while clearing versions.', err);
  }

}

      await RNFS.moveFile(
        TEMP_CONFIG_DIRECTORY + configurationUpdates[i].name,
        CONFIG_DIRECTORY + CONFIG_SUBDIRECTORIES[configurationUpdates[i].type] + configurationUpdates[i].name
      );

      configRowUpdates.push({
        name: configurationUpdates[i].name,
        type: configurationUpdates[i].type,
        version: configurationUpdates[i].newVersion,
      });
    }

    // Delete temporary downloads
    await RNFS.unlink(TEMP_CONFIG_DIRECTORY);

    // Update config versions in database
    await Database.updateConfigVersions(configRowUpdates);

    university = null;
    await module.exports.init();
  } catch (e) {
    throw e;
  }
}

async getItem(key) {
    const filePath = this.psnineFolder + `/${en(key)}.json`
    try {
      const content = await fs.readFile(filePath, 'utf8')
      // console.log(content)
      return content
    } catch (err) {
      // console.log(err)
      return null
    }
  }

shareMessage = () => {
    const { currencyCode, publicAddress } = this.props
    let sharedAddress = this.state.encodedURI
    // if encoded (like XTZ), only share the public address
    if (currencyCode && Constants.getSpecialCurrencyInfo(currencyCode).isUriEncodedStructure) {
      sharedAddress = publicAddress
    }
    const title = sprintf(s.strings.request_qr_email_title, s.strings.app_name, currencyCode)
    const message = sprintf(s.strings.request_qr_email_title, s.strings.app_name, currencyCode) + ': ' + sharedAddress
    const path = Platform.OS === Constants.IOS ? RNFS.DocumentDirectoryPath + '/' + title + '.txt' : RNFS.ExternalDirectoryPath + '/' + title + '.txt'
    RNFS.writeFile(path, message, 'utf8')
      .then(success => {
        const url = Platform.OS === Constants.IOS ? 'file://' + path : ''
        const shareOptions = {
          url,
          title,
          message: sharedAddress
        }
        Share.open(shareOptions).catch(e => console.log(e))
      })
      .catch(showError)
  }