Experimental
This is an experimental technology
Check the Browser compatibility table carefully before using this in production.
The FileSystemFileEntry
interface of the File System API represents a file in a file system. It offers properties describing the file's attributes, as well as the file()
method, which creates a File
object that can be used to read the file.
Properties
Inherits the properties of its parent interface, FileSystemEntry
, but has no properties unique to this interface.
Methods
Obsolete methods
createWriter()
- Creates a new
FileWriter
object which allows writing to the file represented by the file system entry.
Basic concepts
To write content to file, create a FileWriter
object by calling createWriter()
. To read a file, obtain a File
object representing its contents by calling file()
.
Example
The following code creates an empty file called "log.txt"
(if it doesn't exist) and fills it with the text "Meow". Inside the success callback, event handlers are set up to handle the error
error
and writeend
events. The text data is written to the file by creating a blob, appending text to it, and passing the blob to FileWriter.write()
.
function onInitFs(fs) {
fs.root.getFile('log.txt', {create: true}, function(fileEntry) {
// Create a FileWriter object for our FileSystemFileEntry (log.txt).
fileEntry.createWriter(function(fileWriter) {
fileWriter.onwriteend = function(e) {
console.log('Write completed.');
};
fileWriter.onerror = function(e) {
console.log('Write failed: ' + e.toString());
};
// Create a new Blob and write it to log.txt.
var bb = new BlobBuilder();
bb.append('Meow');
fileWriter.write(bb.getBlob('text/plain'));
}, errorHandler);
}, errorHandler);
}
window.requestFileSystem(window.TEMPORARY, 1024*1024, onInitFs, errorHandler);
Specifications
Specification | Status | Comment |
---|---|---|
File and Directory Entries API The definition of 'FileSystemFileEntry' in that specification. |
Draft | Draft of proposed API |
Browser compatibility
BCD tables only load in the browser