FileSystemFileEntry: createWriter() method
Deprecated: This feature is no longer recommended. Though some browsers might still support it, it may have already been removed from the relevant web standards, may be in the process of being dropped, or may only be kept for compatibility purposes. Avoid using it, and update existing code if possible; see the compatibility table at the bottom of this page to guide your decision. Be aware that this feature may cease to work at any time.
Non-standard: This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.
The FileSystemFileEntry
interface's method
createWriter()
returns a FileWriter
object
which can be used to write data into the file represented by the directory entry.
Syntax
js
createWriter(successCallback)
createWriter(successCallback, errorCallback)
Parameters
successCallback
-
A callback function which is called when the
FileWriter
has been created successfully; theFileWriter
is passed into the callback as the only parameter. errorCallback
Optional-
If provided, this must be a method which is called when an error occurs while trying to create the
FileWriter
. This callback receives as input aFileError
object describing the error.
Return value
None (undefined
).
Examples
This example establishes a method, writeToFileEntry()
, which outputs a
text string to the file corresponding to the passed-in directory entry.
js
function writeToFileEntry(entry, text) {
entry.createWriter(
(fileWriter) => {
let data = Blob([text], { type: "text/plain" });
fileWriter.write(data);
},
(fileError) => {
/* do whatever to handle the error */
}
);
}
The success callback for the createWriter()
call takes the text which was
passed in and creates a new Blob
object of type text/plain
that contains the passed text. This blob is then output to the FileWriter
object to be written to the file.
Specifications
This feature is not part of any specification anymore. It is no longer on track to become a standard.
Browser compatibility
BCD tables only load in the browser