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web api instance method

FileSystemEntry: moveTo() method

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The FileSystemEntry interface’s method moveTo() moves the file specified by the entry to a new location on the file system, or renames the file if the destination directory is the same as the source.

There are some typical restrictions on what you can do:

  • A directory can’t be moved into itself.
  • An entry can’t be moved into its parent directory unless you specify a new name. Specifying a new name lets moveTo() double as a rename operation.
  • When moving a directory, the move is always recursive; you can’t leave out subfolders.
  • You can’t move a file such that it replaces an existing directory, and you can’t move a directory such that it replaces an existing file. However, a file can replace a file and a directory can replace a directory.
  • You can only overwrite a directory if it’s empty.

Syntax

moveTo(newParent, newName)
moveTo(newParent, newName, successCallback)
moveTo(newParent, newName, successCallback, errorCallback)

Parameters

  • newParent
  • newName Optional
    • : If this parameter is provided, the entry is renamed to have this string as its new file or directory name.
  • successCallback Optional
    • : A function which is called when the move operation is successfully completed. Receives a single input parameter: a FileSystemEntry based object providing the moved item’s new details.
  • errorCallback Optional
    • : An optional callback which is executed if an error occurs while moving the items. There’s a single parameter: a DOMException describing what went wrong.

Return value

None (undefined).

Exceptions

  • DOMException.INVALID_MODIFICATION_ERR
    • : The requested operation involves an impossible change, such as moving a directory inside itself or one of its own child directories, or copying an item within the same directory without renaming it.
  • DOMException.QUOTA_EXCEEDED_ERR
    • : The operation exceeded the user’s storage quota, or there isn’t enough storage space left to complete the operation.

Examples

This example shows how a temporary log file might be moved into a more permanent “log” directory when it exceeds a megabyte in size.

workingDirectory.getFile(
  "tmp/log.txt",
  {},
  (fileEntry) => {
    fileEntry.getMetadata((metadata) => {
      if (metadata.size > 1048576) {
        workingDirectory.getDirectory(
          "log",
          {},
          (dirEntry) => {
            fileEntry.moveTo(dirEntry);
          },
          handleError,
        );
      }
    });
  },
  handleError,
);

Browser compatibility

Browser compatibilityCompatibility data is available on the canonical MDN page.

See also