• Size of the directory in bytes,
• -1 if an error or an interruption occurred. To get more details on the error, use ErrorInfo with the errMessage constant.

Remark: the hidden files are taken into account when calculating the size of the directory.

Name and full (or relative) path of the directory to use (up to 260 characters). A UNC path can be used. Wildcard characters (*,?) are not allowed.

This parameter can be in Ansi or Unicode format.

This parameter can correspond to a full path or a path relative to the current directory (returned by fCurrentDir). This parameter is case-sensitive.
Reminder: In Android, the file system is read-only on the device and on the emulator. An application can only write to its setup directory or one of its subdirectories, as well as to the external memory (SDCard).

This parameter can correspond to a full path or a path relative to the current directory (returned by fCurrentDir). This parameter is case-sensitive.
Reminder: On iPhone/iPad, the file system is read-only on the device and on the emulator. An application can only write to its setup directory or one of its subdirectories.

Type of iteration performed for the directory files:

fdIgnoreError	If a directory cannot be browsed, it is ignored. If this constant is not specified, fDirSize returns an error.
fdInterruptible	The iteration can be interrupted by pressing ESC. The function will return the name of directories listed until the interruption. This constant has no effect.
frNotRecursive	The iteration is non-recursive. Subdirectories are ignored.
frRecursive (Default value)	The iteration is recursive. Subdirectories are automatically taken into account.