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web api instance method

FileSystemEntry: getMetadata() method

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The FileSystemEntry interface’s method getMetadata() obtains a Metadata object with information about the file system entry, such as its modification date and time and its size.

Syntax

getMetadata(successCallback)
getMetadata(successCallback, errorCallback)

Parameters

  • successCallback
    • : A function which is called when the copy operation is successfully completed. Receives a single input parameter: a Metadata object with information about the file.
  • errorCallback Optional
    • : An optional callback which is executed if an error occurs while looking up the metadata. There’s a single parameter: a DOMException describing what went wrong.

Return value

None (undefined).

Exceptions

  • DOMException.NOT_FOUND_ERR
  • DOMException.SECURITY_ERR
    • : Security restrictions prohibit obtaining the requested metadata.

Examples

This example checks the size of a log file in a temporary folder and, if it exceeds a megabyte, moves it into a different directory.

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