ApplicationData.RoamingFolder | roamingFolder property

Gets the root folder in the roaming app data store.

Syntax

var roamingFolder = applicationData.roamingFolder;

Property value

Type: StorageFolder

The file system folder that contains the files.

Remarks

The sync engine has restrictions on the file name conventions that you must follow to ensure the items in the roaming folder can roam. Be sure that your file and folder names do not contain leading whitespace. The sync engine may limit the total size of settings and files that can roam.

You can access files in the roaming app data store using the "ms-appdata:///roaming/" protocol. For example:

<img src="ms-appdata:///roaming/myFile.png" alt="" />

Windows Phone 8

This API is not implemented and will throw an exception if called.

Examples

Use the file APIs, such as Windows.Storage.StorageFolder.CreateFileAsync | createFileAsync and Windows.Storage.FileIO.WriteTextAsync | writeTextAsync, to create and update a file in the roaming app data store. This example creates a file named dataFile.txt in the roamingFolder container and writes the current date and time to the file. The ReplaceExisting | replaceExisting value from the CreationCollisionOption enumeration indicates that the file should be replaced if it already exists.

Next, this example opens the dataFile.txt file created and reads the date from the file using Windows.Storage.FileIO.readTextAsync.

var applicationData = Windows.Storage.ApplicationData.current;
var roamingFolder = applicationData.roamingFolder;

// Write data to a file

function writeTimestamp() {
   roamingFolder.createFileAsync("dataFile.txt", Windows.Storage.CreationCollisionOption.replaceExisting)
      .then(function (sampleFile) {
         var formatter = new Windows.Globalization.DateTimeFormatting.DateTimeFormatter("longtime");
         var timestamp = formatter.format(new Date());

         return Windows.Storage.FileIO.writeTextAsync(sampleFile, timestamp);
      }).done(function () {      
      });
}

// Read data from a file

function readTimestamp() {
   roamingFolder.getFileAsync("dataFile.txt")
      .then(function (sampleFile) {
         return Windows.Storage.FileIO.readTextAsync(sampleFile);
      }).done(function (timestamp) {
         // Data is contained in timestamp
      }, function () {
         // Timestamp not found
      });
}

Requirements

See also

Tasks

Quickstart: Roaming application data (JavaScript)

Quickstart: Roaming application data (C#/VB/C++)

Concepts

Application data overview

Reference

ApplicationData

Build date: 2/25/2013