1# Copying Files Across Devices 2 3The distributed file system provides the cross-device file copy capability for applications. You can use the [file management APIs](../reference/apis/js-apis-file-fs.md) to copy files across devices and applications. This topic walks you through the process of copying a file from device A to device B. 4 5## How to Develop 6 71. Connect the devices to form a Super Device.<br> 8 Connect the devices to a LAN, and complete device authentication. The devices must be logged in with the same account. 9 102. Copy a file across devices. To copy a file of the same application across devices, place the file in the **distributedfiles/** directory of the application sandbox directory. 11 12 Copy the file of device A from the sandbox directory to the **distributedfiles/** directory of device A. 13 14 ```ts 15 import fs from '@ohos.file.fs'; 16 import common from '@ohos.app.ability.common'; 17 import { BusinessError } from '@ohos.base'; 18 import fileUri from '@ohos.file.fileuri'; 19 20 let context = getContext(this) as common.UIAbilityContext; // Obtain the UIAbilityContext of device A. 21 let pathDir: string = context.filesDir; 22 let distributedPathDir: string = context.distributedFilesDir; 23 // Sandbox directory of the file to copy 24 let filePath: string = pathDir + '/src.txt'; 25 26 try { 27 // If the file does not exist, create a file and write data to the file created. 28 let file = fs.openSync(filePath, fs.OpenMode.CREATE | fs.OpenMode.READ_WRITE); 29 fs.writeSync(file.fd, 'Create file success'); 30 fs.closeSync(file); 31 } catch (err: BusinessError) { 32 console.error(`Failed to createFile. Code: ${err.code}, message: ${err.message}`); 33 } 34 35 // Obtain the URI of the file to copy. 36 let fileUri = fileUri.getUriFromPath(filePath); 37 38 // Copy the file from the sandbox directory to the distributed file directory. 39 let destUri: string = fileUri.getUriFromPath(distributedPathDir + '/src.txt'); 40 41 try { 42 // Copy the file from the sandbox directory to the distributed file directory. 43 fs.copy(fileUri, destUri).then(()=>{ 44 console.info("Succeeded in copying---. "); 45 console.info("src: " + fileUri + "dest: " + destUri); 46 }).catch((err: BusinessError)=>{ 47 console.info(`Failed to copy. Code: ${err.code}, message: ${err.message}`); 48 }) 49 } catch (err: BusinessError) { 50 console.error(`Failed to getData. Code: ${err.code}, message: ${err.message}`); 51 } 52 ``` 53 54 Device B copies the file from the distributed file directory of device B. 55 56 ```ts 57 import fs from '@ohos.file.fs'; 58 import common from '@ohos.app.ability.common'; 59 import { BusinessError } from '@ohos.base'; 60 import fileUri from '@ohos.file.fileuri'; 61 62 let context = getContext(this) as common.UIAbilityContext; // Obtain the UIAbilityContext of device B. 63 let pathDir: string = context.filesDir; 64 let distributedPathDir: string = context.distributedFilesDir; 65 // Destination sandbox directory to which the file is to be copied. 66 let filePath: string = pathDir + '/dest.txt'; 67 68 // Obtain the URI of the destination path. 69 let destUri = fileUri.getUriFromPath(filePath); 70 71 // Obtain the file in the distributed file directory. 72 let srcUri: string = fileUri.getUriFromPath(distributedPathDir + '/src.txt'); 73 74 // Define a callback for the file copy operation. 75 let progressListener: fs.ProgressListener = (progress: fs.Progress) => { 76 console.info(`progressSize: ${progress.processedSize}, totalSize: ${progress.totalSize}`); 77 }; 78 let options: fs.CopyOptions = { 79 "progressListener" : progressListener 80 } 81 82 try { 83 // Copy the file in the distributed file directory to the destination sandbox directory. 84 fs.copy(srcUri, destUri, options).then(()=>{ 85 console.info("Succeeded in copying of paste. "); 86 console.info("src: " + fileUri + "dest: " + destUri); // file://com.example.myapplication/data/storage/el2/distributedfiles/src.txt 87 }).catch((err: BusinessError)=>{ 88 console.info(`Failed to copy. Code: ${err.code}, message: ${err.message}`); 89 }) 90 } catch (err: BusinessError) { 91 console.error(`Failed to copy. Code: ${err.code}, message: ${err.message}`); 92 } 93 ``` 94